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Wang E, Yu B, Zhang J, Gu S, Yang Y, Deng Y, Guo X, Wei B, Bi J, Sun M, Feng H, Song A, Fan F. Low Carbon Loss from Long-Term Manure-Applied Soil during Abrupt Warming Is Realized through Soil and Microbiome Interplay. Environ Sci Technol 2024. [PMID: 38768036 DOI: 10.1021/acs.est.3c08319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Manure application is a global approach for enhancing soil organic carbon (SOC) sequestration. However, the response of SOC decomposition in manure-applied soil to abrupt warming, often occurring during diurnal temperature fluctuations, remains poorly understood. We examined the effects of long-term (23 years) continuous application of manure on SOC chemical composition, soil respiration, and microbial communities under temperature shifts (15 vs 25 °C) in the presence of plant residues. Compared to soil without fertilizer, manure application reduced SOC recalcitrance indexes (i.e., aliphaticity and aromaticity) by 17.45 and 21.77%, and also reduced temperature sensitivity (Q10) of native SOC decomposition, plant residue decomposition, and priming effect by 12.98, 15.98, and 52.83%, respectively. The relative abundances of warm-stimulated chemoheterotrophic bacteria and fungi were lower in the manure-applied soil, whereas those of chemoautotrophic Thaumarchaeota were higher. In addition, the microbial network of the manure-applied soil was more interconnected, with more negative connections with the warm-stimulated taxa than soils without fertilizer or with chemical fertilizer applied. In conclusion, our study demonstrated that the reduced loss of SOC to abrupt warming by manure application arises from C chemistry modification, less warm-stimulated microorganisms, a more complex microbial community, and the higher CO2 intercepting capability by Thaumarchaeota.
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Affiliation(s)
- Enzhao Wang
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Bing Yu
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Jiayin Zhang
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Songsong Gu
- Key Laboratory for Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Yunfeng Yang
- Institute of Environment and Ecology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Ye Deng
- Key Laboratory for Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Xue Guo
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100864, China
| | - Buqing Wei
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Jingjing Bi
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Miaomiao Sun
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Huaqi Feng
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Alin Song
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Fenliang Fan
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
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2
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Cao Y, Du P, Li Z, Xu J, Ma C, Liang B. Melatonin promotes the recovery of apple plants after waterlogging by shaping the structure and function of the rhizosphere microbiome. Plant Cell Environ 2024. [PMID: 38712467 DOI: 10.1111/pce.14903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 03/17/2024] [Accepted: 03/18/2024] [Indexed: 05/08/2024]
Abstract
The dynamics of the physiological adaptability of plants and the rhizosphere soil environment after waterlogging remain unclear. Here we investigated the mechanisms regulating plant condition and shaping of the rhizosphere microbiome in a pot experiment. In the experiment, we added melatonin to waterlogged plants, which promoted waterlogging relief. The treatment significantly enhanced photosynthesis and the antioxidant capacity of apple plants, and significantly promoted nitrogen (N) utilization efficiency by upregulating genes related to N transport and metabolism. Multiperiod soil microbiome analysis showed the dynamic effects of melatonin on the diversity of the microbial community during waterlogging recovery. Random forest and linear regression analyses were used to screen for potential beneficial bacteria (e.g., Azoarcus, Pseudomonas and Nocardioides) specifically regulated by melatonin and revealed a positive correlation with soil nutrient levels and plant growth. Furthermore, metagenomic analyses revealed the regulatory effects of melatonin on genes involved in N cycling in soil. Melatonin positively contributed to the accumulation of plant dry weight by upregulating the expression of nifD and nifK (N fixation). In summary, melatonin positively regulates physiological functions in plants and the structure and function of the microbial community; it promoted the recovery of apple plants after waterlogging stress.
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Affiliation(s)
- Yang Cao
- College of Horticulture, Hebei Agricultural University, Baoding, China
| | - Peihua Du
- College of Horticulture, Hebei Agricultural University, Baoding, China
| | - Zhongyong Li
- College of Horticulture, Hebei Agricultural University, Baoding, China
| | - Jizhong Xu
- College of Horticulture, Hebei Agricultural University, Baoding, China
| | - Changqing Ma
- College of Horticulture, Qingdao Agricultural University, Qingdao, China
| | - Bowen Liang
- College of Horticulture, Hebei Agricultural University, Baoding, China
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3
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Li Y, Sun X, Yang R, Guo L, Li C, Wang X, Li B, Liu H, Wang Q, Soleimani M, Ren Y, Sun W. Phototrophic Nitrogen Fixation, a Neglected Biogeochemical Process in Mine Tailings? Environ Sci Technol 2024; 58:6192-6203. [PMID: 38551467 DOI: 10.1021/acs.est.3c09460] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/10/2024]
Abstract
Biological nitrogen fixation (BNF) has important ecological significance in mine tailing by contributing to the initial accumulation of nitrogen. In addition to chemolithotrophic and heterotrophic BNF, light may also fuel BNF in oligotrophic mine tailings. However, knowledge regarding the occurrence and ecological significance of this biogeochemical process in mine tailings remains ambiguous. The current study observed phototrophic BNF in enrichment cultures established from three primary successional stages (i.e., original tailings, biological crusts, and pioneer plants) of tailings. Notably, phototrophic BNF in tailings may be more active at vegetation stages (i.e., biological crusts and pioneering plants) than in bare tailings. DNA-stable isotope probing identified Roseomonas species as potential aerobic anoxygenic phototrophs responsible for phototrophic BNF. Furthermore, metagenomic binning as well as genome mining revealed that Roseomonas spp. contained essential genes involved in nitrogen fixation, anoxygenic photosynthesis, and carbon fixation, suggesting their genetic potential to mediate phototrophic BNF. A causal inference framework equipped with the structural causal model suggested that the enrichment of putative phototrophic diazotrophic Roseomonas may contribute to an elevated total nitrogen content during primary succession in these mine tailings. Collectively, our findings suggest that phototrophic diazotrophs may play important roles in nutrient accumulation and hold the potential to facilitate ecological succession in tailings.
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Affiliation(s)
- Yongbin Li
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Xiaoxu Sun
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Rui Yang
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Lifang Guo
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Cangbai Li
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, China
| | - Xiaoyu Wang
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Baoqin Li
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Huaqing Liu
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Qi Wang
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Mohsen Soleimani
- Department of Natural Resources, Isfahan University of Technology, Isfahan 84156-83111, Iran
| | - Youhua Ren
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Weimin Sun
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
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4
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Miyajima Y, Aoyagi T, Yoshioka H, Hori T, Takahashi HA, Tanaka M, Tsukasaki A, Goto S, Suzumura M. Impact of Concurrent aerobic-anaerobic Methanotrophy on Methane Emission from Marine Sediments in Gas Hydrate Area. Environ Sci Technol 2024; 58:4979-4988. [PMID: 38445630 PMCID: PMC10956523 DOI: 10.1021/acs.est.3c09484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 02/13/2024] [Accepted: 02/14/2024] [Indexed: 03/07/2024]
Abstract
Microbial methane oxidation has a significant impact on the methane flux from marine gas hydrate areas. However, the environmental fate of methane remains poorly constrained. We quantified the relative contributions of aerobic and anaerobic methanotrophs to methane consumption in sediments of the gas hydrate-bearing Sakata Knoll, Japan, by in situ geochemical and microbiological analyses coupled with 13C-tracer incubation experiments. The anaerobic ANME-1 and ANME-2 species contributed to the oxidation of 33.2 and 1.4% methane fluxes at 0-10 and 10-22 cm below the seafloor (bsf), respectively. Although the aerobic Methylococcaceae species consumed only 0.9% methane flux in the oxygen depleted 0.0-0.5 cmbsf zone, their metabolic activity was sustained down to 6 cmbsf (based on rRNA and lipid biosyntheses), increasing their contribution to 10.3%. Our study emphasizes that the co-occurrence of aerobic and anaerobic methanotrophy at the redox transition zone is an important determinant of methane flux.
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Affiliation(s)
- Yusuke Miyajima
- Research
Institute for Geo-Resources and Environment, Geological Survey of
Japan, National Institute of Advanced Industrial
Science and Technology (AIST), Central 7, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8567, Japan
| | - Tomo Aoyagi
- Environmental
Management Research Institute, National
Institute of Advanced Industrial Science and Technology (AIST), 16-1 Onogawa, Tsukuba, Ibaraki 305-8569, Japan
| | - Hideyoshi Yoshioka
- Research
Institute for Geo-Resources and Environment, Geological Survey of
Japan, National Institute of Advanced Industrial
Science and Technology (AIST), Central 7, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8567, Japan
| | - Tomoyuki Hori
- Environmental
Management Research Institute, National
Institute of Advanced Industrial Science and Technology (AIST), 16-1 Onogawa, Tsukuba, Ibaraki 305-8569, Japan
| | - Hiroshi A. Takahashi
- Research
Institute of Earthquake and Volcano Geology, Geological Survey of
Japan, National Institute of Advanced Industrial
Science and Technology (AIST), Central 7, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8567, Japan
| | - Minako Tanaka
- KANSO
TECHNOS Co., Ltd., 14 Kanda Higashimatsushita-cho, Chiyoda-ku, Tokyo 101-0042, Japan
| | - Ayumi Tsukasaki
- Environmental
Management Research Institute, National
Institute of Advanced Industrial Science and Technology (AIST), 16-1 Onogawa, Tsukuba, Ibaraki 305-8569, Japan
| | - Shusaku Goto
- Research
Institute for Geo-Resources and Environment, Geological Survey of
Japan, National Institute of Advanced Industrial
Science and Technology (AIST), Central 7, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8567, Japan
| | - Masahiro Suzumura
- Environmental
Management Research Institute, National
Institute of Advanced Industrial Science and Technology (AIST), 16-1 Onogawa, Tsukuba, Ibaraki 305-8569, Japan
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5
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Xu K, Tao C, Gu L, Zheng X, Ma Y, Yan Z, Sun Y, Cai Y, Jia Z. Identifying Active Rather than Total Methanotrophs Inhabiting Surface Soil Is Essential for the Microbial Prospection of Gas Reservoirs. Microorganisms 2024; 12:372. [PMID: 38399776 PMCID: PMC10892661 DOI: 10.3390/microorganisms12020372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Revised: 02/08/2024] [Accepted: 02/09/2024] [Indexed: 02/25/2024] Open
Abstract
Methane-oxidizing bacteria (MOB) have long been recognized as an important bioindicator for oil and gas exploration. However, due to their physiological and ecological diversity, the distribution of MOB in different habitats varies widely, making it challenging to authentically reflect the abundance of active MOB in the soil above oil and gas reservoirs using conventional methods. Here, we selected the Puguang gas field of the Sichuan Basin in Southwest China as a model system to study the ecological characteristics of methanotrophs using culture-independent molecular techniques. Initially, by comparing the abundance of the pmoA genes determined by quantitative PCR (qPCR), no significant difference was found between gas well and non-gas well soils, indicating that the abundance of total MOB may not necessarily reflect the distribution of the underlying gas reservoirs. 13C-DNA stable isotope probing (DNA-SIP) in combination with high-throughput sequencing (HTS) furthermore revealed that type II methanotrophic Methylocystis was the absolutely predominant active MOB in the non-gas-field soils, whereas the niche vacated by Methylocystis was gradually filled with type I RPC-2 (rice paddy cluster-2) and Methylosarcina in the surface soils of gas reservoirs after geoscale acclimation to trace- and continuous-methane supply. The sum of the relative abundance of RPC-2 and Methylosarcina was then used as specific biotic index (BI) in the Puguang gas field. A microbial anomaly distribution map based on the BI values showed that the anomalous zones were highly consistent with geological and geophysical data, and known drilling results. Therefore, the active but not total methanotrophs successfully reflected the microseepage intensity of the underlying active hydrocarbon system, and can be used as an essential quantitative index to determine the existence and distribution of reservoirs. Our results suggest that molecular microbial techniques are powerful tools for oil and gas prospecting.
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Affiliation(s)
- Kewei Xu
- State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development, SINOPEC, Beijing 100083, China; (C.T.); (L.G.); (X.Z.); (Y.M.)
- SINOPEC Key Laboratory of Petroleum Accumulation Mechanisms, Wuxi 214126, China
- Wuxi Research Institute of Petroleum Geology, Research Institute of Petroleum Exploration & Production, SINOPEC, Wuxi 214126, China
| | - Cheng Tao
- State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development, SINOPEC, Beijing 100083, China; (C.T.); (L.G.); (X.Z.); (Y.M.)
- SINOPEC Key Laboratory of Petroleum Accumulation Mechanisms, Wuxi 214126, China
- Wuxi Research Institute of Petroleum Geology, Research Institute of Petroleum Exploration & Production, SINOPEC, Wuxi 214126, China
| | - Lei Gu
- State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development, SINOPEC, Beijing 100083, China; (C.T.); (L.G.); (X.Z.); (Y.M.)
- SINOPEC Key Laboratory of Petroleum Accumulation Mechanisms, Wuxi 214126, China
- Wuxi Research Institute of Petroleum Geology, Research Institute of Petroleum Exploration & Production, SINOPEC, Wuxi 214126, China
| | - Xuying Zheng
- State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development, SINOPEC, Beijing 100083, China; (C.T.); (L.G.); (X.Z.); (Y.M.)
- SINOPEC Key Laboratory of Petroleum Accumulation Mechanisms, Wuxi 214126, China
- Wuxi Research Institute of Petroleum Geology, Research Institute of Petroleum Exploration & Production, SINOPEC, Wuxi 214126, China
| | - Yuanyuan Ma
- State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development, SINOPEC, Beijing 100083, China; (C.T.); (L.G.); (X.Z.); (Y.M.)
- SINOPEC Key Laboratory of Petroleum Accumulation Mechanisms, Wuxi 214126, China
- Wuxi Research Institute of Petroleum Geology, Research Institute of Petroleum Exploration & Production, SINOPEC, Wuxi 214126, China
| | - Zhengfei Yan
- School of Biotechnology, Jiangnan University, Wuxi 214122, China;
| | - Yongge Sun
- Department of Earth Science, Zhejiang University, Hangzhou 310027, China;
| | - Yuanfeng Cai
- Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China;
| | - Zhongjun Jia
- Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China;
- State Key Laboratory of Black Soils Conservation and Utilization, Chinese Academy of Sciences, Changchun 130102, China
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6
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Qiao J, Chen M, Zhong S, Tong H, Li F. Soil Humic Acid Stimulates Potentially Active Dissimilatory Arsenate-Reducing Bacteria in Flooded Paddy Soil as Revealed by Metagenomic Stable Isotope Probing. Environ Sci Technol 2024; 58:2303-2312. [PMID: 38263620 DOI: 10.1021/acs.est.3c07753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2024]
Abstract
Dissimilatory arsenate reduction contributes a large proportion of arsenic flux from flooded paddy soil, which is closely linked to soil organic carbon input and efflux. Humic acid (HA) represents a natural ingredient in soil and is shown to enhance microbial arsenate respiration to promote arsenic mobility. However, the community and function profiles of metabolically active arsenate-respiring bacteria and their interactions with HA in paddy soil remain unclear. To probe this linkage, we performed a genome-centric comparison of potentially active arsenate-respiring bacteria in anaerobic microcosms amended with 13C-lactate and HA by combining stable-isotope probing with genome-resolved metagenomics. Indeed, HA greatly accelerated the microbial reduction of arsenate to arsenite. Enrichment of bacteria that harbor arsenate-respiring reductase genes (arrA) in HA-enriched 13C-DNA was confirmed by metagenomic binning, which are affiliated with Firmicutes (mainly Desulfitobacterium, Bacillus, Brevibacillus, and Clostridia) and Acidobacteria. Characterization of reference extracellular electron transfer (EET)-related genes in these arrA-harboring bacteria supports the presence of EET-like genes, with partial electron-transport chain genes identified. This suggests that Gram-positive Firmicutes- and Acidobacteria-related members may harbor unspecified EET-associated genes involved in metal reduction. Our findings highlight the link between soil HA and potentially active arsenate-respiring bacteria, which can be considered when using HA for arsenic removal.
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Affiliation(s)
- Jiangtao Qiao
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangzhou 510650, China
| | - Manjia Chen
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangzhou 510650, China
| | - Songxiong Zhong
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangzhou 510650, China
| | - Hui Tong
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangzhou 510650, China
| | - Fangbai Li
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangzhou 510650, China
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7
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Li W, Baliu-Rodriguez D, Premathilaka SH, Thenuwara SI, Kimbrel JA, Samo TJ, Ramon C, Kiledal EA, Rivera SR, Kharbush J, Isailovic D, Weber PK, Dick GJ, Mayali X. Microbiome processing of organic nitrogen input supports growth and cyanotoxin production of Microcystis aeruginosa cultures. ISME J 2024; 18:wrae082. [PMID: 38718148 PMCID: PMC11126159 DOI: 10.1093/ismejo/wrae082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 04/01/2024] [Accepted: 05/02/2024] [Indexed: 05/26/2024]
Abstract
Nutrient-induced blooms of the globally abundant freshwater toxic cyanobacterium Microcystis cause worldwide public and ecosystem health concerns. The response of Microcystis growth and toxin production to new and recycled nitrogen (N) inputs and the impact of heterotrophic bacteria in the Microcystis phycosphere on these processes are not well understood. Here, using microbiome transplant experiments, cyanotoxin analysis, and nanometer-scale stable isotope probing to measure N incorporation and exchange at single cell resolution, we monitored the growth, cyanotoxin production, and microbiome community structure of several Microcystis strains grown on amino acids or proteins as the sole N source. We demonstrate that the type of organic N available shaped the microbial community associated with Microcystis, and external organic N input led to decreased bacterial colonization of Microcystis colonies. Our data also suggest that certain Microcystis strains could directly uptake amino acids, but with lower rates than heterotrophic bacteria. Toxin analysis showed that biomass-specific microcystin production was not impacted by N source (i.e. nitrate, amino acids, or protein) but rather by total N availability. Single-cell isotope incorporation revealed that some bacterial communities competed with Microcystis for organic N, but other communities promoted increased N uptake by Microcystis, likely through ammonification or organic N modification. Our laboratory culture data suggest that organic N input could support Microcystis blooms and toxin production in nature, and Microcystis-associated microbial communities likely play critical roles in this process by influencing cyanobacterial succession through either decreasing (via competition) or increasing (via biotransformation) N availability, especially under inorganic N scarcity.
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Affiliation(s)
- Wei Li
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA 94550, United States
| | - David Baliu-Rodriguez
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA 94550, United States
- Department of Chemistry and Biochemistry, University of Toledo, Toledo, OH 43606, United States
| | - Sanduni H Premathilaka
- Department of Chemistry and Biochemistry, University of Toledo, Toledo, OH 43606, United States
| | - Sharmila I Thenuwara
- Department of Chemistry and Biochemistry, University of Toledo, Toledo, OH 43606, United States
| | - Jeffrey A Kimbrel
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA 94550, United States
| | - Ty J Samo
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA 94550, United States
| | - Christina Ramon
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA 94550, United States
| | - Erik Anders Kiledal
- Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, MI 48104, United States
| | - Sara R Rivera
- Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, MI 48104, United States
| | - Jenan Kharbush
- Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, MI 48104, United States
| | - Dragan Isailovic
- Department of Chemistry and Biochemistry, University of Toledo, Toledo, OH 43606, United States
| | - Peter K Weber
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA 94550, United States
| | - Gregory J Dick
- Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, MI 48104, United States
- Cooperative Institute for Great Lakes Research, University of Michigan, Ann Arbor, MI 48104, United States
| | - Xavier Mayali
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA 94550, United States
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8
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Hartmann M, Herzog C, Brunner I, Stierli B, Meyer F, Buchmann N, Frey B. Long-term mitigation of drought changes the functional potential and life-strategies of the forest soil microbiome involved in organic matter decomposition. Front Microbiol 2023; 14:1267270. [PMID: 37840720 PMCID: PMC10570739 DOI: 10.3389/fmicb.2023.1267270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Accepted: 09/14/2023] [Indexed: 10/17/2023] Open
Abstract
Climate change can alter the flow of nutrients and energy through terrestrial ecosystems. Using an inverse climate change field experiment in the central European Alps, we explored how long-term irrigation of a naturally drought-stressed pine forest altered the metabolic potential of the soil microbiome and its ability to decompose lignocellulolytic compounds as a critical ecosystem function. Drought mitigation by a decade of irrigation stimulated profound changes in the functional capacity encoded in the soil microbiome, revealing alterations in carbon and nitrogen metabolism as well as regulatory processes protecting microorganisms from starvation and desiccation. Despite the structural and functional shifts from oligotrophic to copiotrophic microbial lifestyles under irrigation and the observation that different microbial taxa were involved in the degradation of cellulose and lignin as determined by a time-series stable-isotope probing incubation experiment with 13C-labeled substrates, degradation rates of these compounds were not affected by different water availabilities. These findings provide new insights into the impact of precipitation changes on the soil microbiome and associated ecosystem functioning in a drought-prone pine forest and will help to improve our understanding of alterations in biogeochemical cycling under a changing climate.
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Affiliation(s)
- Martin Hartmann
- Department of Environmental Systems Science, Sustainable Agroecosystems, Institute of Agricultural Sciences, ETH Zürich, Zürich, Switzerland
- Forest Soils and Biogeochemistry, Swiss Federal Research Institute WSL, Birmensdorf, Switzerland
| | - Claude Herzog
- Forest Soils and Biogeochemistry, Swiss Federal Research Institute WSL, Birmensdorf, Switzerland
- Department of Environmental Systems Science, Grassland Sciences, Institute of Agricultural Sciences, ETH Zürich, Zürich, Switzerland
| | - Ivano Brunner
- Forest Soils and Biogeochemistry, Swiss Federal Research Institute WSL, Birmensdorf, Switzerland
| | - Beat Stierli
- Forest Soils and Biogeochemistry, Swiss Federal Research Institute WSL, Birmensdorf, Switzerland
| | - Folker Meyer
- Data Science, Institute for AI in Medicine, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
- Argonne National Laboratory, Argonne, IL, United States
- Computation Institute, University of Chicago, Chicago, IL, United States
- Department of Medicine, University of Chicago, Chicago, IL, United States
| | - Nina Buchmann
- Department of Environmental Systems Science, Grassland Sciences, Institute of Agricultural Sciences, ETH Zürich, Zürich, Switzerland
| | - Beat Frey
- Forest Soils and Biogeochemistry, Swiss Federal Research Institute WSL, Birmensdorf, Switzerland
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9
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Vyshenska D, Sampara P, Singh K, Tomatsu A, Kauffman WB, Nuccio EE, Blazewicz SJ, Pett-Ridge J, Louie KB, Varghese N, Kellom M, Clum A, Riley R, Roux S, Eloe-Fadrosh EA, Ziels RM, Malmstrom RR. A standardized quantitative analysis strategy for stable isotope probing metagenomics. mSystems 2023; 8:e0128022. [PMID: 37377419 PMCID: PMC10469821 DOI: 10.1128/msystems.01280-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 04/19/2023] [Indexed: 06/29/2023] Open
Abstract
Stable isotope probing (SIP) facilitates culture-independent identification of active microbial populations within complex ecosystems through isotopic enrichment of nucleic acids. Many DNA-SIP studies rely on 16S rRNA gene sequences to identify active taxa, but connecting these sequences to specific bacterial genomes is often challenging. Here, we describe a standardized laboratory and analysis framework to quantify isotopic enrichment on a per-genome basis using shotgun metagenomics instead of 16S rRNA gene sequencing. To develop this framework, we explored various sample processing and analysis approaches using a designed microbiome where the identity of labeled genomes and their level of isotopic enrichment were experimentally controlled. With this ground truth dataset, we empirically assessed the accuracy of different analytical models for identifying active taxa and examined how sequencing depth impacts the detection of isotopically labeled genomes. We also demonstrate that using synthetic DNA internal standards to measure absolute genome abundances in SIP density fractions improves estimates of isotopic enrichment. In addition, our study illustrates the utility of internal standards to reveal anomalies in sample handling that could negatively impact SIP metagenomic analyses if left undetected. Finally, we present SIPmg, an R package to facilitate the estimation of absolute abundances and perform statistical analyses for identifying labeled genomes within SIP metagenomic data. This experimentally validated analysis framework strengthens the foundation of DNA-SIP metagenomics as a tool for accurately measuring the in situ activity of environmental microbial populations and assessing their genomic potential. IMPORTANCE Answering the questions, "who is eating what?" and "who is active?" within complex microbial communities is paramount for our ability to model, predict, and modulate microbiomes for improved human and planetary health. These questions can be pursued using stable isotope probing to track the incorporation of labeled compounds into cellular DNA during microbial growth. However, with traditional stable isotope methods, it is challenging to establish links between an active microorganism's taxonomic identity and genome composition while providing quantitative estimates of the microorganism's isotope incorporation rate. Here, we report an experimental and analytical workflow that lays the foundation for improved detection of metabolically active microorganisms and better quantitative estimates of genome-resolved isotope incorporation, which can be used to further refine ecosystem-scale models for carbon and nutrient fluxes within microbiomes.
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Affiliation(s)
- Dariia Vyshenska
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Pranav Sampara
- Department of Civil Engineering, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Kanwar Singh
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Andy Tomatsu
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - W. Berkeley Kauffman
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Erin E. Nuccio
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California, USA
| | - Steven J. Blazewicz
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California, USA
| | - Jennifer Pett-Ridge
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California, USA
- Life & Environmental Sciences Department, University of California Merced, Merced, California, USA
| | - Katherine B. Louie
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Neha Varghese
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Matthew Kellom
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Alicia Clum
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Robert Riley
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Simon Roux
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Emiley A. Eloe-Fadrosh
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Ryan M. Ziels
- Department of Civil Engineering, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Rex R. Malmstrom
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, California, USA
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10
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Caro TA, McFarlin J, Jech S, Fierer N, Kopf S. Hydrogen stable isotope probing of lipids demonstrates slow rates of microbial growth in soil. Proc Natl Acad Sci U S A 2023; 120:e2211625120. [PMID: 37036980 PMCID: PMC10120080 DOI: 10.1073/pnas.2211625120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Accepted: 03/06/2023] [Indexed: 04/12/2023] Open
Abstract
The rate at which microorganisms grow and reproduce is fundamental to our understanding of microbial physiology and ecology. While soil microbiologists routinely quantify soil microbial biomass levels and the growth rates of individual taxa in culture, there is a limited understanding of how quickly microbes actually grow in soil. For this work, we posed the simple question: what are the growth rates of soil microorganisms? In this study, we measure these rates in three distinct soil environments using hydrogen-stable isotope probing of lipids with 2H-enriched water. This technique provides a taxa-agnostic quantification of in situ microbial growth from the degree of 2H enrichment of intact polar lipid compounds ascribed to bacteria and fungi. We find that growth rates in soil are quite slow and correspond to average generation times of 14 to 45 d but are also highly variable at the compound-specific level (4 to 402 d), suggesting differential growth rates among community subsets. We observe that low-biomass microbial communities exhibit more rapid growth rates than high-biomass communities, highlighting that biomass quantity alone does not predict microbial productivity in soil. Furthermore, within a given soil, the rates at which specific lipids are being synthesized do not relate to their quantity, suggesting a general decoupling of microbial abundance and growth in soil microbiomes. More generally, we demonstrate the utility of lipid-stable isotope probing for measuring microbial growth rates in soil and highlight the importance of measuring growth rates to complement more standard analyses of soil microbial communities.
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Affiliation(s)
- Tristan A. Caro
- Department of Geological Sciences, University of Colorado Boulder, Boulder, CO80309
| | - Jamie McFarlin
- Department of Geology and Geophysics, University of Wyoming, Laramie, WY82071
| | - Sierra Jech
- Department of Ecology and Evolutionary Biology, University of Colorado Boulder, Boulder, CO80309
| | - Noah Fierer
- Department of Ecology and Evolutionary Biology, University of Colorado Boulder, Boulder, CO80309
- Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, Boulder, CO80309
| | - Sebastian Kopf
- Department of Geological Sciences, University of Colorado Boulder, Boulder, CO80309
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11
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Barnett SE, Egan R, Foster B, Eloe-Fadrosh EA, Buckley DH. Genomic Features Predict Bacterial Life History Strategies in Soil, as Identified by Metagenomic Stable Isotope Probing. mBio 2023;:e0358422. [PMID: 36877031 DOI: 10.1128/mbio.03584-22] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2023] Open
Abstract
Bacteria catalyze the formation and destruction of soil organic matter, but the bacterial dynamics in soil that govern carbon (C) cycling are not well understood. Life history strategies explain the complex dynamics of bacterial populations and activities based on trade-offs in energy allocation to growth, resource acquisition, and survival. Such trade-offs influence the fate of soil C, but their genomic basis remains poorly characterized. We used multisubstrate metagenomic DNA stable isotope probing to link genomic features of bacteria to their C acquisition and growth dynamics. We identify several genomic features associated with patterns of bacterial C acquisition and growth, notably genomic investment in resource acquisition and regulatory flexibility. Moreover, we identify genomic trade-offs defined by numbers of transcription factors, membrane transporters, and secreted products, which match predictions from life history theory. We further show that genomic investment in resource acquisition and regulatory flexibility can predict bacterial ecological strategies in soil. IMPORTANCE Soil microbes are major players in the global carbon cycle, yet we still have little understanding of how the carbon cycle operates in soil communities. A major limitation is that carbon metabolism lacks discrete functional genes that define carbon transformations. Instead, carbon transformations are governed by anabolic processes associated with growth, resource acquisition, and survival. We use metagenomic stable isotope probing to link genome information to microbial growth and carbon assimilation dynamics as they occur in soil. From these data, we identify genomic traits that can predict bacterial ecological strategies which define bacterial interactions with soil carbon.
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12
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Bokade P, Bajaj A. Molecular advances in mycoremediation of polycyclic aromatic hydrocarbons: Exploring fungal bacterial interactions. J Basic Microbiol 2023; 63:239-256. [PMID: 36670077 DOI: 10.1002/jobm.202200499] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 11/15/2022] [Accepted: 12/18/2022] [Indexed: 01/22/2023]
Abstract
Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous high global concern environmental pollutants and tend to bioaccumulate due to hydrophobic properties. These xenobiotics, having variable concentrations along different matrices, gradually undergo various physical, chemical, and biological transformation processes. Myco-remediation aids accelerated degradation by effectively transforming complex ring structures to oxidized/hydroxylated intermediates, which can further funnel to bacterial degradation pathways. Exploitation of such complementing fungal-bacterial enzymatic activity can overcome certain limitations of incomplete bioremediation process. Furthermore, high-throughput molecular methods can be employed to unveil community structure, taxon abundance, coexisting community interactions, and metabolic pathways under stressed conditions. The present review critically discusses the role of different fungal phyla in PAHs biotransformation and application of fungal-bacterial cocultures for enhanced mineralization. Moreover, recent advances in bioassays for PAH residue detection, monitoring, developing xenobiotics stress-tolerant strains, and application of fungal catabolic enzymes are highlighted. Application of next-generation sequencing methods to reveal complex ecological networks based on microbial community interactions and data analysis bias in performing such studies is further discussed in detail. Conclusively, the review underscores the application of mixed-culture approach by critically highlighting in situ fungal-bacterial community nexus and its role in complete mineralization of PAHs for the management of contaminated sites.
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Affiliation(s)
- Priyanka Bokade
- Environmental Biotechnology and Genomics Division, CSIR-National Environmental Engineering Research Institute (CSIR-NEERI), Nagpur, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Abhay Bajaj
- Environmental Biotechnology and Genomics Division, CSIR-National Environmental Engineering Research Institute (CSIR-NEERI), Nagpur, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
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13
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Cui L, Xin Y, Yang K, Li H, Tan F, Zhang Y, Li X, Zhu Z, Yang J, Kao SJ, Ren B, Zhu YG, Musat F, Musat N. Live tracking metabolic networks and physiological responses within microbial assemblages at single-cell level. PNAS Nexus 2023; 2:pgad006. [PMID: 36896131 PMCID: PMC9991459 DOI: 10.1093/pnasnexus/pgad006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 12/27/2022] [Accepted: 01/03/2023] [Indexed: 01/20/2023]
Abstract
Microbial interactions impact the functioning of both natural and engineered systems, yet our ability to directly monitor these highly dynamic and spatially resolved interactions in living cells is very limited. Here, we developed a synergistic approach coupling single-cell Raman microspectroscopy with 15N2 and 13CO2 stable isotope probing in a microfluidic culture system (RMCS-SIP) for live tracking of the occurrence, rate, and physiological shift of metabolic interactions in active microbial assemblages. Quantitative and robust Raman biomarkers specific for N2 and CO2 fixation in both model and bloom-forming diazotrophic cyanobacteria were established and cross-validated. By designing a prototype microfluidic chip allowing simultaneous microbial cultivation and single-cell Raman acquisition, we achieved temporal tracking of both intercellular (between heterocyst and vegetative cells of cyanobacteria) and interspecies N and C metabolite exchange (from diazotroph to heterotroph). Moreover, single-cell N and C fixation and bidirectional transfer rate in living cells were quantified via SIP-induced characteristic Raman shifts. Remarkably, RMCS captured physiological responses of metabolically active cells to nutrient stimuli through comprehensive metabolic profiling, providing multimodal information on the evolution of microbial interactions and functions under fluctuating conditions. This noninvasive RMCS-SIP is an advantageous approach for live-cell imaging and represents an important advancement in the single-cell microbiology field. This platform can be extended for real-time tracking of a wide range of microbial interactions with single-cell resolution and advances the understanding and manipulation of microbial interactions for societal benefit.
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Affiliation(s)
- Li Cui
- Key Lab of Urban Environment and Health, Fujian Key Laboratory of Watershed Ecology, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Yuhan Xin
- Key Lab of Urban Environment and Health, Fujian Key Laboratory of Watershed Ecology, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Kai Yang
- Key Lab of Urban Environment and Health, Fujian Key Laboratory of Watershed Ecology, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Hongzhe Li
- Key Lab of Urban Environment and Health, Fujian Key Laboratory of Watershed Ecology, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Fengjiao Tan
- Key Lab of Urban Environment and Health, Fujian Key Laboratory of Watershed Ecology, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Yulong Zhang
- Pen-Tung Sah Institute of Micro-Nano Science and Technology, Xiamen University, Xiamen 361005, China
| | - Xingrui Li
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Zhi Zhu
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Jun Yang
- Key Lab of Urban Environment and Health, Fujian Key Laboratory of Watershed Ecology, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Shuh-Ji Kao
- College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, China
| | - Bin Ren
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Yong-Guan Zhu
- Key Lab of Urban Environment and Health, Fujian Key Laboratory of Watershed Ecology, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Florin Musat
- Department of Molecular Biology and Biotechnology, Faculty of Biology and Geology, Babeş-Bolyai University, Cluj-Napoca 400084, Romania
| | - Niculina Musat
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Leipzig 04318, Germany
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14
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Li Y, Guo L, Kolton M, Yang R, Zhang M, Qi F, Soleimani M, Sun X, Li B, Gao W, Yan G, Xu R, Sun W. Chemolithotrophic Biological Nitrogen Fixation Fueled by Antimonite Oxidation May Be Widespread in Sb-Contaminated Habitats. Environ Sci Technol 2023; 57:231-243. [PMID: 36525577 DOI: 10.1021/acs.est.2c06424] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Nitrogen (N) deficiency in mining-contaminated habitats usually hinders plant growth and thus hampers tailing revegetation. Biological N fixation (BNF) is an essential biogeochemical process that contributes to the initial accumulation of N in oligotrophic mining-contaminated regions. Previous studies reported that chemolithotrophic rather than heterotrophic diazotrophs frequently dominated in the mining-contaminated regions. Chemolithotrophic diazotrophs may utilize elements abundant in such habitats (e.g., sulfur (S), arsenic (As), and antimony (Sb)) as electron donors to fix N2. BNF fueled by the oxidation of S and As has been detected in previous studies. However, BNF fueled by Sb(III) oxidation (Sb-dependent BNF) has never been reported. The current study observed the presence of Sb-dependent BNF in slurries inoculated from Sb-contaminated habitats across the South China Sb belt, suggesting that Sb-dependent BNF may be widespread in this region. DNA-stable isotope probing identified bacteria associated with Rhodocyclaceae and Rhizobiaceae as putative microorganisms responsible for Sb-dependent BNF. Furthermore, metagenomic-binning demonstrated that Rhodocyclaceae and Rhizobiaceae contained essential genes involved in Sb(III) oxidation, N2 fixation, and carbon fixation, suggesting their genetic potential for Sb-dependent BNF. In addition, meta-analysis indicated that these bacteria are widespread among Sb-contaminated habitats with different niche preferences: Rhodocyclaceae was enriched in river sediments and tailings, while Rhizobiaceae was enriched only in soils. This study may broaden our fundamental understanding of N fixation in Sb-mining regions.
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Affiliation(s)
- Yongbin Li
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Lifang Guo
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Max Kolton
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
- French Associates Institute for Agriculture and Biotechnology of Drylands, Ben-Gurion University of the Negev, Beer Sheva 84105, Israel
| | - Rui Yang
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Miaomiao Zhang
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Fangjie Qi
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Mohsen Soleimani
- Department of Natural Resources, Isfahan University of Technology, Isfahan 83111-84156, Iran
| | - Xiaoxu Sun
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Baoqin Li
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Wenlong Gao
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
- Hainan Key Laboratory of Tropical Eco-Circular Agriculture, Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China
- Hainan Danzhou Tropical Agro-ecosystem National Observation and Research Station, Danzhou 571737, China
| | - Geng Yan
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Rui Xu
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Weimin Sun
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
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15
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Greenlon A, Sieradzki E, Zablocki O, Koch BJ, Foley MM, Kimbrel JA, Hungate BA, Blazewicz SJ, Nuccio EE, Sun CL, Chew A, Mancilla CJ, Sullivan MB, Firestone M, Pett-Ridge J, Banfield JF. Quantitative Stable-Isotope Probing (qSIP) with Metagenomics Links Microbial Physiology and Activity to Soil Moisture in Mediterranean-Climate Grassland Ecosystems. mSystems 2022; 7:e0041722. [PMID: 36300946 DOI: 10.1128/msystems.00417-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The growth and physiology of soil microorganisms, which play vital roles in biogeochemical cycling, are shaped by both current and historical soil environmental conditions. Here, we developed and applied a genome-resolved metagenomic implementation of quantitative stable isotope probing (qSIP) with an H218O labeling experiment to identify actively growing soil microorganisms and their genomic capacities. qSIP enabled measurement of taxon-specific growth because isotopic incorporation into microbial DNA requires production of new genome copies. We studied three Mediterranean grassland soils across a rainfall gradient to evaluate the hypothesis that historic precipitation levels are an important factor controlling trait selection. We used qSIP-informed genome-resolved metagenomics to resolve the active subset of soil community members and identify their characteristic ecophysiological traits. Higher year-round precipitation levels correlated with higher activity and growth rates of flagellar motile microorganisms. In addition to heavily isotopically labeled bacteria, we identified abundant isotope-labeled phages, suggesting phage-induced cell lysis likely contributed to necromass production at all three sites. Further, there was a positive correlation between phage activity and the activity of putative phage hosts. Contrary to our expectations, the capacity to decompose the diverse complex carbohydrates common in soil organic matter or oxidize methanol and carbon monoxide were broadly distributed across active and inactive bacteria in all three soils, implying that these traits are not highly selected for by historical precipitation. IMPORTANCE Soil moisture is a critical factor that strongly shapes the lifestyle of soil organisms by changing access to nutrients, controlling oxygen diffusion, and regulating the potential for mobility. We identified active microorganisms in three grassland soils with similar mineral contexts, yet different historic rainfall inputs, by adding water labeled with a stable isotope and tracking that isotope in DNA of growing microbes. By examining the genomes of active and inactive microorganisms, we identified functions that are enriched in growing organisms, and showed that different functions were selected for in different soils. Wetter soil had higher activity of motile organisms, but activity of pathways for degradation of soil organic carbon compounds, including simple carbon substrates, were comparable for all three soils. We identified many labeled, and thus active bacteriophages (viruses that infect bacteria), implying that the cells they killed contributed to soil organic matter. The activity of these bacteriophages was significantly correlated with activity of their hosts.
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16
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Kröber E, Mankowski A, Schäfer H. Microorganisms associated with Sporobolus anglicus, an invasive dimethylsulfoniopropionate producing salt marsh plant, are an unrecognized sink for dimethylsulfide. Front Microbiol 2022; 13:950460. [PMID: 36246216 PMCID: PMC9563715 DOI: 10.3389/fmicb.2022.950460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2022] [Accepted: 08/12/2022] [Indexed: 11/23/2022] Open
Abstract
Background Saltmarshes are hotspots of organosulfur compound cycling due to production of dimethylsulfoniopropionate (DMSP) by benthic microorganisms, macroalgae, and saltmarsh vegetation. Degradation of DMSP is a source of dimethylsulfide (DMS), an important precursor for formation of secondary organic aerosol. Microorganisms degrading DMS play a role in controlling the amount of DMS available for emission into the atmosphere. Previous work has implicated sediment microbial populations as a major sink for DMS. Here, we show that Sporobolus anglicus (previously known as Spartina anglica), a widely distributed saltmarsh plant, is colonized by DMS-degrading microorganisms. Methods Dimethylsulfide degradation potential was assessed by gas chromatography and 13C-DMS stable isotope probing, microbial community diversity and functional genetic potential in phyllosphere and rhizosphere samples was assessed by high-throughput sequencing of 16S rRNA gene amplicons, cloning and sequencing of methanethiol oxidase genes, and by metagenomic analysis of phyllosphere microbial communities. Results The DMS degradation potential of microbial communities recovered from phyllosphere and rhizosphere samples was similar. Active DMS-degraders were identified by 13C-DMS stable isotope probing and included populations related to Methylophaga and other Piscirickettsiaceae in rhizosphere samples. DMS-degraders in the phyllosphere included Xanthomonadaceae and Halothiobacillaceae. The diversity in sediment samples of the methanethiol oxidase (mtoX) gene, a marker for metabolism of methanethiol during DMS and DMSP degradation, was similar to previously detected saltmarsh mtoX, including those of Methylophaga and Methylococcaeae. Phyllosphere mtoX genes were distinct from sediment mtoX and did not include close relatives of cultivated bacteria. Microbial diversity in the phyllosphere of S. anglicus was distinct compared to those of model plants such as rice, soybean, clover and Arabidopsis and showed a dominance of Gammaproteobacteria rather than Alphaproteobacteria. Conclusion The potential for microbial DMS degradation in the phyllosphere and rhizosphere of Sporobolus anglicus suggest that DMS cycling in saltmarshes is more complex than previously recognised and calls for a more detailed assessment of how aboveground activities affect fluxes of DMS.
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Affiliation(s)
- Eileen Kröber
- School of Life Sciences, Gibbet Hill Campus, University of Warwick, Coventry, United Kingdom
- Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Anna Mankowski
- Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Hendrik Schäfer
- School of Life Sciences, Gibbet Hill Campus, University of Warwick, Coventry, United Kingdom
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17
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Luo J, Gu S, Guo X, Liu Y, Tao Q, Zhao HP, Liang Y, Banerjee S, Li T. Core Microbiota in the Rhizosphere of Heavy Metal Accumulators and Its Contribution to Plant Performance. Environ Sci Technol 2022; 56:12975-12987. [PMID: 36067360 DOI: 10.1021/acs.est.1c08832] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Persistent microbial symbioses can confer greater fitness to their host under unfavorable conditions, but manipulating such beneficial interactions necessitates a mechanistic understanding of the consistently important microbiomes for the plant. Here, we examined the phylogenetic profiles and plant-beneficial traits of the core microbiota that consistently inhabits the rhizosphere of four divergent Cd hyperaccumulators and an accumulator. We evidenced the existence of a conserved core rhizosphere microbiota in each plant distinct from that in the non-hyperaccumulating plant. Members of Burkholderiaceae and Sphingomonas were the shared cores across hyperaccumulators and accumulators. Several keystone taxa in the rhizosphere networks were part of the core microbiota, the abundance of which was an important predictor of plant Cd accumulation. Furthermore, an inoculation experiment with synthetic communities comprising isolates belonging to the shared cores indicated that core microorganisms could facilitate plant growth and metal tolerance. Using RNA-based stable isotope probing, we discovered that abundant core taxa overlapped with active rhizobacteria utilizing root exudates, implying that the core rhizosphere microbiota assimilating plant-derived carbon may provide benefits to plant growth and host phenotype such as Cd accumulation. Our study suggests common principles underpinning hyperaccumulator-microbiome interactions, where plants consistently interact with a core set of microbes contributing to host fitness and plant performance. These findings lay the foundation for harnessing the persistent root microbiomes to accelerate the restoration of metal-disturbed soils.
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Affiliation(s)
- Jipeng Luo
- Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Shaohua Gu
- Center for Quantitative Biology and Peking-Tsinghua Center for Life Sciences, Peking University, 100091 Beijing, China
| | - Xinyu Guo
- Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yuankun Liu
- Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Qi Tao
- College of Resources, Sichuan Agricultural University, Chengdu 611130, China
| | - He-Ping Zhao
- Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yongchao Liang
- Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Samiran Banerjee
- Department of Microbiological Sciences, North Dakota State University, Fargo, North Dakota 58108-6050, United States
| | - Tingqiang Li
- Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
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18
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Zhu QZ, Wegener G, Hinrichs KU, Elvert M. Activity of Ancillary Heterotrophic Community Members in Anaerobic Methane-Oxidizing Cultures. Front Microbiol 2022; 13:912299. [PMID: 35722308 PMCID: PMC9201399 DOI: 10.3389/fmicb.2022.912299] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Accepted: 05/02/2022] [Indexed: 11/13/2022] Open
Abstract
Consortia of anaerobic methanotrophic archaea (ANME) and sulfate-reducing bacteria mediate the anaerobic oxidation of methane (AOM) in marine sediments. However, even sediment-free cultures contain a substantial number of additional microorganisms not directly related to AOM. To track the heterotrophic activity of these community members and their possible relationship with AOM, we amended meso- (37°C) and thermophilic (50°C) AOM cultures (dominated by ANME-1 archaea and their partner bacteria of the Seep-SRB2 clade or Candidatus Desulfofervidus auxilii) with L-leucine-3-13C (13C-leu). Various microbial lipids incorporated the labeled carbon from this amino acid, independent of the presence of methane as an energy source, specifically bacterial fatty acids, such as iso and anteiso-branched C15:0 and C17:0, as well as unsaturated C18:1ω9 and C18:1ω7. In natural methane-rich environments, these bacterial fatty acids are strongly 13C-depleted. We, therefore, suggest that those fatty acids are produced by ancillary bacteria that grow on 13C-depleted necromass or cell exudates/lysates of the AOM core communities. Candidates that likely benefit from AOM biomass are heterotrophic bacterial members of the Spirochetes and Anaerolineae—known to produce abundant branched fatty acids and present in all the AOM enrichment cultures. For archaeal lipids, we observed minor 13C-incorporation, but still suggesting some 13C-leu anabolism. Based on their relatively high abundance in the culture, the most probable archaeal candidates are Bathyarchaeota, Thermoplasmatales, and Lokiarchaeota. The identified heterotrophic bacterial and archaeal ancillary members are likely key players in organic carbon recycling in anoxic marine sediments.
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Affiliation(s)
- Qing-Zeng Zhu
- MARUM - Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | - Gunter Wegener
- MARUM - Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany.,Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Kai-Uwe Hinrichs
- MARUM - Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany.,Faculty of Geosciences, University of Bremen, Bremen, Germany
| | - Marcus Elvert
- MARUM - Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany.,Faculty of Geosciences, University of Bremen, Bremen, Germany
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19
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Geesink P, Taubert M, Jehmlich N, von Bergen M, Küsel K. Bacterial Necromass Is Rapidly Metabolized by Heterotrophic Bacteria and Supports Multiple Trophic Levels of the Groundwater Microbiome. Microbiol Spectr 2022;:e0043722. [PMID: 35699474 DOI: 10.1128/spectrum.00437-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Pristine groundwater is a highly stable environment with microbes adapted to dark, oligotrophic conditions. Input events like heavy rainfalls can introduce the excess particulate organic matter, including surface-derived microorganisms, thereby disturbing the groundwater microbiome. Some surface-derived bacteria will not survive this translocation, leading to an input of necromass to the groundwater. Here, we investigated the effects of necromass addition to the microbial community in fractured bedrock groundwater, using groundwater mesocosms as model systems. We followed the uptake of 13C-labeled necromass by the bacterial and eukaryotic groundwater community quantitatively and over time using a complementary protein-stable and DNA-stable isotope probing approach. Necromass was rapidly depleted in the mesocosms within 4 days, accompanied by a strong decrease in Shannon diversity and a 10-fold increase in bacterial 16S rRNA gene copy numbers. Species of Flavobacterium, Massilia, Rheinheimera, Rhodoferax, and Undibacterium dominated the microbial community within 2 days and were identified as key players in necromass degradation, based on a 13C incorporation of >90% in their peptides. Their proteomes comprised various proteins for uptake and transport functions and amino acid metabolization. After 4 and 8 days, the autotrophic and mixotrophic taxa Nitrosomonas, Limnohabitans, Paucibacter, and Acidovorax increased in abundance with a 13C incorporation between 0.5% and 23%. Likewise, eukaryotes assimilated necromass-derived carbon either directly or indirectly. Our data point toward a fast and exclusive uptake of labeled necromass by a few specialists followed by a concerted action of groundwater microorganisms, including autotrophs presumably fueled by released, reduced nitrogen and sulfur compounds generated during necromass degradation. IMPORTANCE Subsurface microbiomes provide essential ecosystem services, like the generation of drinking water. These ecosystems are devoid of light-driven primary production, and microbial life is adapted to the resulting oligotrophic conditions. Modern groundwater is most vulnerable to anthropogenic and climatic impacts. Heavy rainfalls, which will increase with climate change, can result in high surface inputs into shallow aquifers by percolation or lateral flow. These inputs include terrestrial organic matter and surface-derived microbes that are not all capable to flourish in aquatic subsurface habitats. Here, we investigated the response of groundwater mesocosms to the addition of bacterial necromass, simulating event-driven surface input. We found that the groundwater microbiome responds with a rapid bloom of only a few primary degraders, followed by the activation of typical groundwater autotrophs and mixotrophs, as well as eukaryotes. Our results suggest that this multiphase strategy is essential to maintain the balance of the groundwater microbiome to provide ecosystem services.
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20
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Cao W, Cai Y, Bao Z, Wang S, Yan X, Jia Z. Methanotrophy Alleviates Nitrogen Constraint of Carbon Turnover by Rice Root-Associated Microbiomes. Front Microbiol 2022; 13:885087. [PMID: 35663885 PMCID: PMC9159908 DOI: 10.3389/fmicb.2022.885087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Accepted: 04/21/2022] [Indexed: 11/23/2022] Open
Abstract
The bioavailability of nitrogen constrains primary productivity, and ecosystem stoichiometry implies stimulation of N2 fixation in association with carbon sequestration in hotspots such as paddy soils. In this study, we show that N2 fixation was triggered by methane oxidation and the methanotrophs serve as microbial engines driving the turnover of carbon and nitrogen in rice roots. 15N2-stable isotope probing showed that N2-fixing activity was stimulated 160-fold by CH4 oxidation from 0.27 to 43.3 μmol N g–1 dry weight root biomass, and approximately 42.5% of the fixed N existed in the form of 15N-NH4+ through microbial mineralization. Nitrate amendment almost completely abolished N2 fixation. Ecophysiology flux measurement indicated that methane oxidation-induced N2 fixation contributed only 1.9% of total nitrogen, whereas methanotrophy-primed mineralization accounted for 21.7% of total nitrogen to facilitate root carbon turnover. DNA-based stable isotope probing further indicated that gammaproteobacterial Methylomonas-like methanotrophs dominated N2 fixation in CH4-consuming roots, whereas nitrate addition resulted in the shift of the active population to alphaproteobacterial Methylocystis-like methanotrophs. Co-occurring pattern analysis of active microbial community further suggested that a number of keystone taxa could have played a major role in nitrogen acquisition through root decomposition and N2 fixation to facilitate nutrient cycling while maintaining soil productivity. This study thus highlights the importance of root-associated methanotrophs as both biofilters of greenhouse gas methane and microbial engines of bioavailable nitrogen for rice growth.
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Affiliation(s)
- Weiwei Cao
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Yuanfeng Cai
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, China
| | - Zhihua Bao
- Ministry of Education Key Laboratory of Ecology and Resource Use of the Mongolian Plateau & Inner Mongolia Key Laboratory of Grassland Ecology, School of Ecology and Environment, Inner Mongolia University, Hohhot, China.,Inner Mongolia Key Laboratory of Environmental Pollution Control and Waste Resource Reuse, Inner Mongolia University, Hohhot, China
| | - Shuwei Wang
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, China
| | - Xiaoyuan Yan
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, China
| | - Zhongjun Jia
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, China.,University of Chinese Academy of Sciences, Beijing, China
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21
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Vuillemin A, Coskun ÖK, Orsi WD. Microbial Activities and Selection from Surface Ocean to Subseafloor on the Namibian Continental Shelf. Appl Environ Microbiol 2022; 88:e0021622. [PMID: 35404072 DOI: 10.1128/aem.00216-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Oxygen minimum zones (OMZs) are hot spots for redox-sensitive nitrogen transformations fueled by sinking organic matter. In comparison, the regulating role of sulfur-cycling microbes in marine OMZs, their impact on carbon cycling in pelagic and benthic habitats, and activities below the seafloor remain poorly understood. Using 13C DNA stable isotope probing (SIP) and metatranscriptomics, we explored microbial guilds involved in sulfur and carbon cycling from the ocean surface to the subseafloor on the Namibian shelf. There was a clear separation in microbial community structure across the seawater-seafloor boundary, which coincided with a 100-fold-increased concentration of microbial biomass and unique gene expression profiles of the benthic communities. 13C-labeled 16S rRNA genes in SIP experiments revealed carbon-assimilating taxa and their distribution across the sediment-water interface. Most of the transcriptionally active taxa among water column communities that assimilated 13C from diatom exopolysaccharides (mostly Bacteroidetes, Actinobacteria, Alphaproteobacteria, and Planctomycetes) also assimilated 13C-bicarbonate under anoxic conditions in sediment incubations. Moreover, many transcriptionally active taxa from the seafloor community (mostly sulfate-reducing Deltaproteobacteria and sulfide-oxidizing Gammaproteobacteria) that assimilated 13C-bicarbonate under sediment anoxic conditions also assimilated 13C from diatom exopolysaccharides in the surface ocean and OMZ waters. Despite strong selection at the sediment-water interface, many taxa related to either planktonic or benthic communities were found to be present at low abundance and actively assimilating carbon under both sediment and water column conditions. In austral winter, mixing of shelf waters reduces stratification and suspends sediments from the seafloor into the water column, potentially spreading metabolically versatile microbes across niches. IMPORTANCE Microbial activities in oxygen minimum zones (OMZs) transform inorganic fixed nitrogen into greenhouse gases, impacting the Earth’s climate and nutrient equilibrium. Coastal OMZs are predicted to expand with global change and increase carbon sedimentation to the seafloor. However, the role of sulfur-cycling microbes in assimilating carbon in marine OMZs and related seabed habitats remain poorly understood. Using 13C DNA stable isotope probing and metatranscriptomics, we explore microbial guilds involved in sulfur and carbon cycling from ocean surface to subseafloor on the Namibian shelf. Despite strong selection and differential activities across the sediment-water interface, many active taxa were identified in both planktonic and benthic communities, either fixing inorganic carbon or assimilating organic carbon from algal biomass. Our data show that many planktonic and benthic microbes linked to the sulfur cycle can cross redox boundaries when mixing of the shelf waters reduces stratification and suspends seafloor sediment particles into the water column.
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22
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Shu X, Zou Y, Shaw LJ, Todman L, Tibbett M, Sizmur T. Applying cover crop residues as diverse mixtures increases initial microbial assimilation of crop residue-derived carbon. Eur J Soil Sci 2022; 73:e13232. [PMID: 35909880 PMCID: PMC9311145 DOI: 10.1111/ejss.13232] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2021] [Revised: 02/28/2022] [Accepted: 03/04/2022] [Indexed: 06/12/2023]
Abstract
UNLABELLED Increasing the diversity of crops grown in arable soils delivers multiple ecological functions. Whether mixtures of residues from different crops grown in polyculture contribute to microbial assimilation of carbon (C) to a greater extent than would be expected from applying individual residues is currently unknown. In this study, we used 13C isotope labelled cover crop residues (buckwheat, clover, radish, and sunflower) to track microbial assimilation of plant residue-derived C using phospholipid fatty acid (PLFA) analysis. We also quantified microbial assimilation of C derived from the soil organic matter (SOM) because fresh residue inputs also prime the decomposition of SOM. To consider the initial stages of residue decomposition, and preclude microbial turnover, we compared a quaternary mixture of residues with the average effect of their four components 1 day after incorporation. Our results show that the microbial biomass carbon (MBC) in the treatment receiving the mixed residue was significantly greater, by 132% (3.61 μg C g-1), than the mean plant residue-derived MBC in treatments receiving the four individual components of the mixture. However, there was no evidence that the mixture resulted in any additional assimilation of C derived from native SOM than the average observed in individual residue treatments. We surmise that, during the initial stages of crop residue decomposition, a greater biodiversity of residues increases microbial assimilation to a greater extent than would be expected from applying individual residues either due to faster decomposition or greater carbon use efficiency (CUE). This might be facilitated by functional complementarity in the soil microbiota, permitted by a greater diversity of substrates, reducing competition for any single substrate. Therefore, growing and incorporating crop polycultures (e.g., cover crop mixtures) could be an effective method to increase microbial C assimilation in the early stages of cover crop decomposition. HIGHLIGHTS The effect of mixing crop residues on assimilation of C by soil microbial biomass was investigated.The study is important due to recent interest in diverse cover crop mixtures for arable systems.Mixing crop residues enhanced the assimilation of plant residue-derived C into microbial biomass.Growing and incorporating cover crop polycultures may enhance C storage in arable soils.
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Affiliation(s)
- Xin Shu
- Soil Research Centre, Department of Geography and Environmental ScienceUniversity of ReadingReadingUK
| | - Yiran Zou
- Soil Research Centre, Department of Geography and Environmental ScienceUniversity of ReadingReadingUK
| | - Liz J. Shaw
- Soil Research Centre, Department of Geography and Environmental ScienceUniversity of ReadingReadingUK
| | - Lindsay Todman
- Soil Research Centre, Department of Sustainable Land Management, School of Agriculture, Policy and DevelopmentUniversity of ReadingReadingUK
| | - Mark Tibbett
- Soil Research Centre, Department of Sustainable Land Management, School of Agriculture, Policy and DevelopmentUniversity of ReadingReadingUK
| | - Tom Sizmur
- Soil Research Centre, Department of Geography and Environmental ScienceUniversity of ReadingReadingUK
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23
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Li Y, Guo L, Häggblom MM, Yang R, Li M, Sun X, Chen Z, Li F, Su X, Yan G, Xiao E, Zhang H, Sun W. Serratia spp. Are Responsible for Nitrogen Fixation Fueled by As(III) Oxidation, a Novel Biogeochemical Process Identified in Mine Tailings. Environ Sci Technol 2022; 56:2033-2043. [PMID: 35006678 DOI: 10.1021/acs.est.1c06857] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Biological nitrogen fixation (BNF) has important environmental implications in tailings by providing bioavailable nitrogen to these habitats and sustaining ecosystem functions. Previously, chemolithotrophic diazotrophs that dominate in mine tailings were shown to use reduced sulfur (S) as the electron donor. Tailings often contain high concentrations of As(III) that might function as an alternative electron donor to fuel BNF. Here, we tested this hypothesis and report on BNF fueled by As(III) oxidation as a novel biogeochemical process in addition to BNF fueled by S. Arsenic (As)-dependent BNF was detected in cultures inoculated from As-rich tailing samples derived from the Xikuangshan mining area in China, as suggested by nitrogenase activity assays, quantitative polymerase chain reaction, and 15N2 enrichment incubations. As-dependent BNF was also active in eight other As-contaminated tailings and soils, suggesting that the potential for As-dependent BNF may be widespread in As-rich habitats. DNA-stable isotope probing identified Serratia spp. as the bacteria responsible for As-dependent BNF. Metagenomic binning indicated that the essential genes for As-dependent BNF [i.e., nitrogen fixation, As(III) oxidation, and carbon fixation] were present in Serratia-associated metagenome-assembled genomes. Over 20 Serratia genomes obtained from NCBI also contained essential genes for both As(III) oxidation and BNF (i.e., aioA and nifH), suggesting that As-dependent BNF may be a widespread metabolic trait in Serratia spp.
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Affiliation(s)
- Yongbin Li
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Lifang Guo
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Max M Häggblom
- Department of Biochemistry and Microbiology, Rutgers University, New Brunswick New Jersey 08901, United States
| | - Rui Yang
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Mengyan Li
- Department of Chemistry and Environmental Science, New Jersey Institute of Technology, Newark New Jersey 07102, United States
| | - Xiaoxu Sun
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Zheng Chen
- Department of Health and Environmental Sciences, Xi'an Jiaotong-Liverpool University, Suzhou 215123, China
| | - Fangbai Li
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Xianfa Su
- School of Environment, Key Laboratory of Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, Henan Normal University, Xinxiang 453007, P. R. China
| | - Geng Yan
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Enzong Xiao
- Innovation Center and Key Laboratory of Waters Safety & Protection in the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, P.R. China
| | - Haihan Zhang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Weimin Sun
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
- Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
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Polerecky L, Eichner M, Masuda T, Zavřel T, Rabouille S, Campbell DA, Halsey K. Calculation and Interpretation of Substrate Assimilation Rates in Microbial Cells Based on Isotopic Composition Data Obtained by nanoSIMS. Front Microbiol 2021; 12:621634. [PMID: 34917040 PMCID: PMC8670600 DOI: 10.3389/fmicb.2021.621634] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Accepted: 11/08/2021] [Indexed: 11/17/2022] Open
Abstract
Stable isotope probing (SIP) combined with nano-scale secondary ion mass spectrometry (nanoSIMS) is a powerful approach to quantify assimilation rates of elements such as C and N into individual microbial cells. Here, we use mathematical modeling to investigate how the derived rate estimates depend on the model used to describe substrate assimilation by a cell during a SIP incubation. We show that the most commonly used model, which is based on the simplifying assumptions of linearly increasing biomass of individual cells over time and no cell division, can yield underestimated assimilation rates when compared to rates derived from a model that accounts for cell division. This difference occurs because the isotopic labeling of a dividing cell increases more rapidly over time compared to a non-dividing cell and becomes more pronounced as the labeling increases above a threshold value that depends on the cell cycle stage of the measured cell. Based on the modeling results, we present formulae for estimating assimilation rates in cells and discuss their underlying assumptions, conditions of applicability, and implications for the interpretation of intercellular variability in assimilation rates derived from nanoSIMS data, including the impacts of storage inclusion metabolism. We offer the formulae as a Matlab script to facilitate rapid data evaluation by nanoSIMS users.
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Affiliation(s)
- Lubos Polerecky
- Department of Earth Sciences, Utrecht University, Utrecht, Netherlands
| | - Meri Eichner
- Institute of Microbiology, Czech Academy of Sciences, Centre Algatech, Třeboň, Czechia
| | - Takako Masuda
- Institute of Microbiology, Czech Academy of Sciences, Centre Algatech, Třeboň, Czechia
| | - Tomáš Zavřel
- Global Change Research Institute, Czech Academy of Sciences, Brno, Czechia
| | - Sophie Rabouille
- Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefranche, LOV, Villefranche-sur-mer, France.,Sorbonne Université, CNRS, Laboratoire d'Océanographie Microbienne, LOMIC, Banyuls-sur-mer, France
| | | | - Kimberly Halsey
- Department of Microbiology, Oregon State University, Corvallis, OR, United States
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Yakubovskaya E, Zaliznyak T, Martínez JM, Taylor GT. Raman Microspectroscopy Goes Viral: Infection Dynamics in the Cosmopolitan Microalga, Emiliania huxleyi. Front Microbiol 2021; 12:686287. [PMID: 34795644 PMCID: PMC8593419 DOI: 10.3389/fmicb.2021.686287] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Accepted: 10/12/2021] [Indexed: 11/18/2022] Open
Abstract
Emiliania huxleyi is a cosmopolitan member of the marine phytoplankton. This species’ capacities for carbon sequestration and sulfur mobilization make it a key player in oceanic biogeochemical cycles that influence climate on a planetary scale. Seasonal E. huxleyi blooms are abruptly terminated by viral epidemics caused by a clade of large DNA viruses collectively known as coccolithoviruses (EhVs). EhVs thereby mediate a significant part of material and energy fluxes associated with E. huxleyi population dynamics. In this study, we use spontaneous Raman microspectroscopy to perform label-free and non-invasive measurements of the macromolecular composition of individual virions and E. huxleyi host cells. Our novel autofluorescence suppression protocol enabled spectroscopic visualization of evolving macromolecular redistributions in individual E. huxleyi cells at different stages of EhV infection. Material transfer from E. huxleyi hosts to single EhV-163 virions was confirmed by combining stable isotope probing (SIP) experiments with Raman microspectroscopy. Inheritance of the host cells’ 13C-enriched isotopic signature was quantified based on red shifts of Raman peaks characteristic of phenylalanine’s phenyl ring. Two-dimensional Raman mapping of EhV-infected E. huxleyi cells revealed that the compact region producing an intense Raman DNA signal (i.e., the nucleus) in healthy E. huxleyi cells becomes diffuse during the first hours of infection. Raman DNA emissions integrated throughout individual cells decreased during the infection cycle. Our observations are consistent with EhV-163 degrading the host’s nuclear DNA, scavenging released nucleotides for its own genome replication, and shedding newly-produced virions prior to host lysis via budding.
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Affiliation(s)
- Elena Yakubovskaya
- School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY, United States
| | - Tatiana Zaliznyak
- School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY, United States
| | | | - Gordon T Taylor
- School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY, United States
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Yu GH, Kuzyakov Y, Luo Y, Goodman BA, Kappler A, Liu FF, Sun FS. Molybdenum Bioavailability and Asymbiotic Nitrogen Fixation in Soils are Raised by Iron (Oxyhydr)oxide-Mediated Free Radical Production. Environ Sci Technol 2021; 55:14979-14989. [PMID: 34677955 DOI: 10.1021/acs.est.1c04240] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Nitrogen (N) fixation in soils is closely linked to microbially mediated molybdenum (Mo) cycling. Therefore, elucidating the mechanisms and factors that affect Mo bioavailability is crucial for understanding N fixation. Here, we demonstrate that long-term (26 years) manure fertilization increased microbial diversity and content of short-range ordered iron (oxyhydr)oxides that raised Mo bioavailability (by 2.8 times) and storage (by ∼30%) and increased the abundance of nifH genes (by ∼14%) and nitrogenase activity (by ∼60%). Nanosized iron (oxyhydr)oxides (ferrihydrite, goethite, and hematite nanoparticles) play a dual role in soil Mo cycling: (i) in concert with microorganisms, they raise Mo bioavailability by catalyzing hydroxyl radical (HO•) production via the Fenton reactions and (ii) they increase Mo retention by association with the nanosized iron (oxyhydr)oxides. In summary, long-term manure fertilization raised the stock and bioavailability of Mo (and probably also of other micronutrients) by increasing iron (oxyhydr)oxide reactivity and intensified asymbiotic N fixation through an increased abundance of nifH genes and nitrogenase activity. This work provides a strategy for increasing biological N fixation in agricultural ecosystems.
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Affiliation(s)
- Guang-Hui Yu
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai Rim, Tianjin University, Tianjin 300072, China
| | - Yakov Kuzyakov
- Department of Soil Science of Temperate Ecosystems, Department of Agricultural Soil Science, University of Göttingen, Göttingen 37073, Germany
- Agro-Technological Institute, RUDN University, Moscow 117198, Russia
| | - Yu Luo
- Institute of Soil and Water Resources and Environmental Science, Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Zhejiang University, Hangzhou 310058, China
| | - Bernard A Goodman
- College of Physical Science and Technology, Guangxi University, Nanning 530004, China
| | - Andreas Kappler
- Geomicrobiology, Center for Applied Geosciences, University of Tübingen, Tübingen 72076, Germany
- Cluster of Excellence: EXC 2124: Controlling Microbes to Fight Infections, Tübingen 72076, Germany
| | - Fei-Fei Liu
- College of Resources & Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Fu-Sheng Sun
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai Rim, Tianjin University, Tianjin 300072, China
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27
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Weber F, Zaliznyak T, Edgcomb VP, Taylor GT. Using Stable Isotope Probing and Raman Microspectroscopy To Measure Growth Rates of Heterotrophic Bacteria. Appl Environ Microbiol 2021; 87:e0146021. [PMID: 34495689 DOI: 10.1128/AEM.01460-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The suitability of stable isotope probing (SIP) and Raman microspectroscopy to measure growth rates of heterotrophic bacteria at the single-cell level was evaluated. Label assimilation into Escherichia coli biomass during growth on a complex 13C-labeled carbon source was monitored in time course experiments. 13C incorporation into various biomolecules was measured by spectral "red shifts" of Raman-scattered emissions. The 13C- and 12C-isotopologues of the amino acid phenylalanine (Phe) proved to be quantitatively accurate reporter molecules of cellular isotopic fractional abundances (fcell). Values of fcell determined by Raman microspectroscopy and independently by isotope ratio mass spectrometry (IRMS) over a range of isotopic enrichments were statistically indistinguishable. Progressive labeling of Phe in E. coli cells among a range of 13C/12C organic substrate admixtures occurred predictably through time. The relative isotopologue abundances of Phe determined by Raman spectral analysis enabled the accurate calculation of bacterial growth rates as confirmed independently by optical density (OD) measurements. The results demonstrate that combining SIP and Raman microspectroscopy can be a powerful tool for studying bacterial growth at the single-cell level on defined or complex organic 13C carbon sources, even in mixed microbial assemblages. IMPORTANCE Population growth dynamics and individual cell growth rates are the ultimate expressions of a microorganism's fitness under its environmental conditions, whether natural or engineered. Natural habitats and many industrial settings harbor complex microbial assemblages. Their heterogeneity in growth responses to existing and changing conditions is often difficult to grasp by standard methodologies. In this proof-of-concept study, we tested whether Raman microspectroscopy can reliably quantify the assimilation of isotopically labeled nutrients into E. coli cells and enable the determination of individual growth rates among heterotrophic bacteria. Raman-derived growth rate estimates were statistically indistinguishable from those derived by standard optical density measurements of the same cultures. Raman microspectroscopy can also be combined with methods for phylogenetic identification. We report the development of Raman-based techniques that enable researchers to directly link genetic identity to functional traits and rate measurements of single cells within mixed microbial assemblages, currently a major technical challenge in microbiological research.
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Dekas AE. Quantifying Microbial Activity In Situ: the Link between Cells and Cycles. mSystems 2021; 6:e0075821. [PMID: 34463583 DOI: 10.1128/msystems.00758-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Metagenomic sequencing of environmental samples has dramatically expanded our knowledge of microbial taxonomic and metabolic diversity and suggests metabolic interdependence is widespread. However, translating these insights into knowledge of ecosystem function and, therefore, implications for local and global chemistry, remains a challenge. In this commentary, I argue that making direct measurements of microbial activity in situ is an essential step to confirm gene-based hypotheses of microbial physiology and bridge advances in microbial ecology with a predicative understanding of global chemistry and climate. Making these measurements across a range of spatial scales and experimentally manipulated conditions contributes to a process-based understanding and, therefore, more robust predictions of how activity will respond to changing environmental conditions. I discuss recent advancements in quantifying microbial activity in situ and highlight several lines of research in marine microbiology that leverage complementary genomic and isotopic methods to connect microbes and global chemistry.
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Affiliation(s)
- Anne E Dekas
- Earth System Science Department, Stanford University, Stanford, California, USA
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Godon JJ, Bize A, Ngo H, Cauquil L, Almeida M, Petit MA, Zemb O. Bacterial Consumption of T4 Phages. Microorganisms 2021; 9:microorganisms9091852. [PMID: 34576747 PMCID: PMC8472381 DOI: 10.3390/microorganisms9091852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 08/23/2021] [Accepted: 08/24/2021] [Indexed: 11/25/2022] Open
Abstract
The bacterial consumption of viruses not been reported on as of yet even though bacteria feed on almost anything. Viruses are widely distributed but have no acknowledged active biocontrol. Viral biomass undoubtedly reintegrates trophic cycles; however, the mechanisms of this phase still remain unknown. 13C-labelled T4 phages monitor the increase of the density of the bacterial DNA concomitant with the decrease of plaque forming units. We used 12C T4 phages as a control. T4 phage disappearance in wastewater sludge was found to occur mainly through predation by Aeromonadacea. Phage consumption also favours significant in situ bacterial growth. Furthermore, an isolated strain of Aeromonas was observed to grow on T4 phages as sole the source of carbon, nitrogen, and phosphorus. Bacterial species are capable of consuming bacteriophages in situ, which is likely a widespread and underestimated type of biocontrol. This assay is anticipated as a starting point for harnessing the bacterial potential in limiting the diffusion of harmful viruses within environments such as in the gut or in water.
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Affiliation(s)
- Jean-Jacques Godon
- INRAE, Univ Montpellier, LBE, 11100 Narbonne, France
- Correspondence: (J.-J.G.); (O.Z.); Tel.: +33-4-68-42-51-54 (J.-J.G.); +33-5-61-28-50-99 (O.Z.)
| | - Ariane Bize
- PRocédés biOtechnologiques au Service de l’Environnement, INRAE, Université Paris-Saclay, 92761 Antony, France; (A.B.); (H.N.)
| | - Hoang Ngo
- PRocédés biOtechnologiques au Service de l’Environnement, INRAE, Université Paris-Saclay, 92761 Antony, France; (A.B.); (H.N.)
| | - Laurent Cauquil
- GenPhySE, INRAE, Université de Toulouse, 31320 Castanet-Tolosan, France;
| | - Mathieu Almeida
- MGP, INRAE, Université Paris-Saclay, 78350 Jouy-en-Josas, France;
| | - Marie-Agnès Petit
- AgroParisTech, Micalis Institute, INRAE, Université Paris-Saclay, 78350 Jouy-en-Josas, France
| | - Olivier Zemb
- GenPhySE, INRAE, Université de Toulouse, 31320 Castanet-Tolosan, France;
- Correspondence: (J.-J.G.); (O.Z.); Tel.: +33-4-68-42-51-54 (J.-J.G.); +33-5-61-28-50-99 (O.Z.)
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Lee S, Sieradzki ET, Nicolas AM, Walker RL, Firestone MK, Hazard C, Nicol GW. Methane-derived carbon flows into host-virus networks at different trophic levels in soil. Proc Natl Acad Sci U S A 2021; 118:e2105124118. [PMID: 34349022 DOI: 10.1073/pnas.2105124118] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The concentration of atmospheric methane (CH4) continues to increase with microbial communities controlling soil-atmosphere fluxes. While there is substantial knowledge of the diversity and function of prokaryotes regulating CH4 production and consumption, their active interactions with viruses in soil have not been identified. Metagenomic sequencing of soil microbial communities enables identification of linkages between viruses and hosts. However, this does not determine if these represent current or historical interactions nor whether a virus or host are active. In this study, we identified active interactions between individual host and virus populations in situ by following the transfer of assimilated carbon. Using DNA stable-isotope probing combined with metagenomic analyses, we characterized CH4-fueled microbial networks in acidic and neutral pH soils, specifically primary and secondary utilizers, together with the recent transfer of CH4-derived carbon to viruses. A total of 63% of viral contigs from replicated soil incubations contained homologs of genes present in known methylotrophic bacteria. Genomic sequences of 13C-enriched viruses were represented in over one-third of spacers in CRISPR arrays of multiple closely related Methylocystis populations and revealed differences in their history of viral interaction. Viruses infecting nonmethanotrophic methylotrophs and heterotrophic predatory bacteria were also identified through the analysis of shared homologous genes, demonstrating that carbon is transferred to a diverse range of viruses associated with CH4-fueled microbial food networks.
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Abstract
The conventional microbial cell analyses are mostly population-averaged methods that conceal the characteristics of single-cell in the community. Single-cell analysis can provide information on the functional and structural variation of each cell, resulting in the elimination of long and tedious microbial cultivation techniques. Raman spectroscopy is a label-free, noninvasive, and in-vivo method ideal for single-cell measurement to obtain spatially resolved chemical information. In the current review, recent developments in Raman spectroscopic techniques for microbial characterization at the single-cell level are presented, focusing on Raman imaging of single cells to study the intracellular distribution of different components. The review also discusses the limitation and challenges of each technique and put forward some future outlook for improving Raman spectroscopy-based techniques for single-cell analysis. Raman spectroscopic methods at the single-cell level have potential in precision measurements, metabolic analysis, antibiotic susceptibility testing, resuscitation capability, and correlating phenotypic information to genomics for cells, the integration of Raman spectroscopy with other techniques such as microfluidics, stable isotope probing (SIP), and atomic force microscope can further improve the resolution and provide extensive information. Future focuses should be given to advance algorithms for data analysis, standardized reference libraries, and automated cell isolation techniques in future.
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Affiliation(s)
- Heera Jayan
- School of Food Science and Engineering, South China University of Technology, Guangzhou 510641, China.,Academy of Contemporary Food Engineering, South China University of Technology, Guangzhou Higher Education Mega Center, Guangzhou 510641, China.,Engineering and Technological Research Centre of Guangdong Province on Intelligent Sensing and Process Control of Cold Chain Foods, and Guangdong Province Engineering Laboratory for Intelligent Cold Chain Logistics Equipment for Agricultural Products, Guangzhou Higher Education Mega Centre, Guangzhou 510006, China
| | - Hongbin Pu
- School of Food Science and Engineering, South China University of Technology, Guangzhou 510641, China.,Academy of Contemporary Food Engineering, South China University of Technology, Guangzhou Higher Education Mega Center, Guangzhou 510641, China.,Engineering and Technological Research Centre of Guangdong Province on Intelligent Sensing and Process Control of Cold Chain Foods, and Guangdong Province Engineering Laboratory for Intelligent Cold Chain Logistics Equipment for Agricultural Products, Guangzhou Higher Education Mega Centre, Guangzhou 510006, China
| | - Da-Wen Sun
- School of Food Science and Engineering, South China University of Technology, Guangzhou 510641, China.,Academy of Contemporary Food Engineering, South China University of Technology, Guangzhou Higher Education Mega Center, Guangzhou 510641, China.,Engineering and Technological Research Centre of Guangdong Province on Intelligent Sensing and Process Control of Cold Chain Foods, and Guangdong Province Engineering Laboratory for Intelligent Cold Chain Logistics Equipment for Agricultural Products, Guangzhou Higher Education Mega Centre, Guangzhou 510006, China.,Food Refrigeration and Computerized Food Technology (FRCFT), Agriculture and Food Science Centre, University College Dublin, National University of Ireland, Dublin 4, Ireland
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Li Q, Cooper RE, Wegner CE, Taubert M, Jehmlich N, von Bergen M, Küsel K. Insights into Autotrophic Activities and Carbon Flow in Iron-Rich Pelagic Aggregates (Iron Snow). Microorganisms 2021; 9:1368. [PMID: 34201891 DOI: 10.3390/microorganisms9071368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 06/18/2021] [Accepted: 06/21/2021] [Indexed: 11/17/2022] Open
Abstract
Pelagic aggregates function as biological carbon pumps for transporting fixed organic carbon to sediments. In iron-rich (ferruginous) lakes, photoferrotrophic and chemolithoautotrophic bacteria contribute to CO2 fixation by oxidizing reduced iron, leading to the formation of iron-rich pelagic aggregates (iron snow). The significance of iron oxidizers in carbon fixation, their general role in iron snow functioning and the flow of carbon within iron snow is still unclear. Here, we combined a two-year metatranscriptome analysis of iron snow collected from an acidic lake with protein-based stable isotope probing to determine general metabolic activities and to trace 13CO2 incorporation in iron snow over time under oxic and anoxic conditions. mRNA-derived metatranscriptome of iron snow identified four key players (Leptospirillum, Ferrovum, Acidithrix, Acidiphilium) with relative abundances (59.6-85.7%) encoding ecologically relevant pathways, including carbon fixation and polysaccharide biosynthesis. No transcriptional activity for carbon fixation from archaea or eukaryotes was detected. 13CO2 incorporation studies identified active chemolithoautotroph Ferrovum under both conditions. Only 1.0-5.3% relative 13C abundances were found in heterotrophic Acidiphilium and Acidocella under oxic conditions. These data show that iron oxidizers play an important role in CO2 fixation, but the majority of fixed C will be directly transported to the sediment without feeding heterotrophs in the water column in acidic ferruginous lakes.
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Sieradzki ET, Morando M, Fuhrman JA. Metagenomics and Quantitative Stable Isotope Probing Offer Insights into Metabolism of Polycyclic Aromatic Hydrocarbon Degraders in Chronically Polluted Seawater. mSystems 2021; 6:e00245-21. [PMID: 33975968 PMCID: PMC8125074 DOI: 10.1128/msystems.00245-21] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 04/12/2021] [Indexed: 11/21/2022] Open
Abstract
Bacterial biodegradation is a significant contributor to remineralization of polycyclic aromatic hydrocarbons (PAHs)-toxic and recalcitrant components of crude oil as well as by-products of partial combustion chronically introduced into seawater via atmospheric deposition. The Deepwater Horizon oil spill demonstrated the speed at which a seed PAH-degrading community maintained by chronic inputs responds to acute pollution. We investigated the diversity and functional potential of a similar seed community in the chronically polluted Port of Los Angeles (POLA), using stable isotope probing with naphthalene, deep-sequenced metagenomes, and carbon incorporation rate measurements at the port and in two sites in the San Pedro Channel. We demonstrate the ability of the community of degraders at the POLA to incorporate carbon from naphthalene, leading to a quick shift in microbial community composition to be dominated by the normally rare Colwellia and Cycloclasticus We show that metagenome-assembled genomes (MAGs) belonged to these naphthalene degraders by matching their 16S-rRNA gene with experimental stable isotope probing data. Surprisingly, we did not find a full PAH degradation pathway in those genomes, even when combining genes from the entire microbial community, leading us to hypothesize that promiscuous dehydrogenases replace canonical naphthalene degradation enzymes in this site. We compared metabolic pathways identified in 29 genomes whose abundance increased in the presence of naphthalene to generate genomic-based recommendations for future optimization of PAH bioremediation at the POLA, e.g., ammonium as opposed to urea, heme or hemoproteins as an iron source, and polar amino acids.IMPORTANCE Oil spills in the marine environment have a devastating effect on marine life and biogeochemical cycles through bioaccumulation of toxic hydrocarbons and oxygen depletion by hydrocarbon-degrading bacteria. Oil-degrading bacteria occur naturally in the ocean, especially where they are supported by chronic inputs of oil or other organic carbon sources, and have a significant role in degradation of oil spills. Polycyclic aromatic hydrocarbons are the most persistent and toxic component of crude oil. Therefore, the bacteria that can break those molecules down are of particular importance. We identified such bacteria at the Port of Los Angeles (POLA), one of the busiest ports worldwide, and characterized their metabolic capabilities. We propose chemical targets based on those analyses to stimulate the activity of these bacteria in case of an oil spill in the Port POLA.
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Affiliation(s)
- Ella T Sieradzki
- Department of Biological Sciences, University of Southern California, Los Angeles, California, USA
| | - Michael Morando
- Department of Biological Sciences, University of Southern California, Los Angeles, California, USA
| | - Jed A Fuhrman
- Department of Biological Sciences, University of Southern California, Los Angeles, California, USA
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He X, Chadwick GL, Kempes CP, Orphan VJ, Meile C. Controls on Interspecies Electron Transport and Size Limitation of Anaerobically Methane-Oxidizing Microbial Consortia. mBio 2021; 12:e03620-20. [PMID: 33975943 DOI: 10.1128/mBio.03620-20] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
About 382 Tg yr−1 of methane rising through the seafloor is oxidized anaerobically (W. S. Reeburgh, Chem Rev 107:486–513, 2007, https://doi.org/10.1021/cr050362v), preventing it from reaching the atmosphere, where it acts as a strong greenhouse gas. Microbial consortia composed of anaerobic methanotrophic archaea and sulfate-reducing bacteria couple the oxidation of methane to the reduction of sulfate under anaerobic conditions via a syntrophic process. Recent experimental studies and modeling efforts indicate that direct interspecies electron transfer (DIET) is involved in this syntrophy. Here, we explore a fluorescent in situ hybridization-nanoscale secondary ion mass spectrometry data set of large, segregated anaerobic oxidation of methane (AOM) consortia that reveal a decline in metabolic activity away from the archaeal-bacterial interface and use a process-based model to identify the physiological controls on rates of AOM. Simulations reproducing the observational data reveal that ohmic resistance and activation loss are the two main factors causing the declining metabolic activity, where activation loss dominated at a distance of <8 μm. These voltage losses limit the maximum spatial distance between syntrophic partners with model simulations, indicating that sulfate-reducing bacterial cells can remain metabolically active up to ∼30 μm away from the archaeal-bacterial interface. Model simulations further predict that a hybrid metabolism that combines DIET with a small contribution of diffusive exchange of electron donors can offer energetic advantages for syntrophic consortia.
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35
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Hungate BA, Marks JC, Power ME, Schwartz E, van Groenigen KJ, Blazewicz SJ, Chuckran P, Dijkstra P, Finley BK, Firestone MK, Foley M, Greenlon A, Hayer M, Hofmockel KS, Koch BJ, Mack MC, Mau RL, Miller SN, Morrissey EM, Propster JR, Purcell AM, Sieradzki E, Starr EP, Stone BWG, Terrer C, Pett-Ridge J. The Functional Significance of Bacterial Predators. mBio 2021; 12:e00466-21. [PMID: 33906922 PMCID: PMC8092244 DOI: 10.1128/mbio.00466-21] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Accepted: 03/02/2021] [Indexed: 02/07/2023] Open
Abstract
Predation structures food webs, influences energy flow, and alters rates and pathways of nutrient cycling through ecosystems, effects that are well documented for macroscopic predators. In the microbial world, predatory bacteria are common, yet little is known about their rates of growth and roles in energy flows through microbial food webs, in part because these are difficult to quantify. Here, we show that growth and carbon uptake were higher in predatory bacteria compared to nonpredatory bacteria, a finding across 15 sites, synthesizing 82 experiments and over 100,000 taxon-specific measurements of element flow into newly synthesized bacterial DNA. Obligate predatory bacteria grew 36% faster and assimilated carbon at rates 211% higher than nonpredatory bacteria. These differences were less pronounced for facultative predators (6% higher growth rates, 17% higher carbon assimilation rates), though high growth and carbon assimilation rates were observed for some facultative predators, such as members of the genera Lysobacter and Cytophaga, both capable of gliding motility and wolf-pack hunting behavior. Added carbon substrates disproportionately stimulated growth of obligate predators, with responses 63% higher than those of nonpredators for the Bdellovibrionales and 81% higher for the Vampirovibrionales, whereas responses of facultative predators to substrate addition were no different from those of nonpredators. This finding supports the ecological theory that higher productivity increases predator control of lower trophic levels. These findings also indicate that the functional significance of bacterial predators increases with energy flow and that predatory bacteria influence element flow through microbial food webs.IMPORTANCE The word "predator" may conjure images of leopards killing and eating impala on the African savannah or of great white sharks attacking elephant seals off the coast of California. But microorganisms are also predators, including bacteria that kill and eat other bacteria. While predatory bacteria have been found in many environments, it has been challenging to document their importance in nature. This study quantified the growth of predatory and nonpredatory bacteria in soils (and one stream) by tracking isotopically labeled substrates into newly synthesized DNA. Predatory bacteria were more active than nonpredators, and obligate predators, such as Bdellovibrionales and Vampirovibrionales, increased in growth rate in response to added substrates at the base of the food chain, strong evidence of trophic control. This work provides quantitative measures of predator activity and suggests that predatory bacteria-along with protists, nematodes, and phages-are active and important in microbial food webs.
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Affiliation(s)
- Bruce A Hungate
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
- Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona, USA
| | - Jane C Marks
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
- Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona, USA
| | - Mary E Power
- Department of Integrative Biology, University of California Berkeley, Berkeley, California, USA
| | - Egbert Schwartz
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
- Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona, USA
| | - Kees Jan van Groenigen
- Department of Geography, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
| | - Steven J Blazewicz
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California, USA
| | - Peter Chuckran
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
- Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona, USA
| | - Paul Dijkstra
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
- Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona, USA
| | - Brianna K Finley
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
- Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona, USA
| | - Mary K Firestone
- Department of Environmental Science, Policy, and Management, University of California, Berkeley, California, USA
| | - Megan Foley
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
- Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona, USA
| | - Alex Greenlon
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California, USA
| | - Michaela Hayer
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
| | - Kirsten S Hofmockel
- Pacific Northwest National Laboratory, Richland, Washington, USA
- Department of Agronomy, Iowa State University, Ames, Iowa, USA
| | - Benjamin J Koch
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
- Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona, USA
| | - Michelle C Mack
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
- Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona, USA
| | - Rebecca L Mau
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
- Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, Arizona, USA
| | - Samantha N Miller
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
| | - Ember M Morrissey
- Division of Plant and Soil Sciences, West Virginia University, Morgantown, West Virginia, USA
| | - Jeffrey R Propster
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
- Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona, USA
| | - Alicia M Purcell
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
- Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona, USA
| | - Ella Sieradzki
- Department of Environmental Science, Policy, and Management, University of California, Berkeley, California, USA
| | - Evan P Starr
- Department of Plant and Microbial Biology, University of California, Berkeley, California, USA
| | - Bram W G Stone
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
| | - César Terrer
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California, USA
| | - Jennifer Pett-Ridge
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California, USA
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Zhang M, Kolton M, Li Z, Lin H, Li F, Lu G, Gao P, Sun X, Xu R, Xu F, Sun W. Bacteria responsible for antimonite oxidation in antimony-contaminated soil revealed by DNA-SIP coupled to metagenomics. FEMS Microbiol Ecol 2021; 97:6206827. [PMID: 33791784 DOI: 10.1093/femsec/fiab057] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Accepted: 03/29/2021] [Indexed: 12/23/2022] Open
Abstract
Antimony (Sb), the analog of arsenic (As), is a toxic metalloid that poses risks to the environment and human health. Antimonite (Sb(III)) oxidation can decrease Sb toxicity, which contributes to the bioremediation of Sb contamination. Bacteria can oxidize Sb(III), but the current knowledge regarding Sb(III)-oxidizing bacteria (SbOB) is limited to pure culture studies, thus underestimating the diversity of SbOB. In this study, Sb(III)-oxidizing microcosms were set up using Sb-contaminated rice paddies as inocula. Sb(III) oxidation driven by microorganisms was observed in the microcosms. The increasing copies and transcription of the arsenate-oxidizing gene, aioA, in the microcosms during biotic Sb(III) oxidation indicated that microorganisms mediated Sb(III) oxidation via the aioA genes. Furthermore, a novel combination of DNA-SIP and shotgun metagenomic was applied to identify the SbOB and predict their metabolic potential. Several putative SbOB were identified, including Paracoccus, Rhizobium, Achromobacter and Hydrogenophaga. Furthermore, the metagenomic analysis indicated that all of these putative SbOB contained aioA genes, confirming their roles in Sb(III) oxidation. These results suggested the concept of proof of combining DNA-SIP and shotgun metagenomics directly. In addition, the identification of the novel putative SbOB expands the current knowledge regarding the diversity of SbOB.
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Affiliation(s)
- Miaomiao Zhang
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China.,Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Max Kolton
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China.,Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Zhe Li
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China.,Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Hanzhi Lin
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China.,Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Fangbai Li
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China.,Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Guimei Lu
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China.,Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Pin Gao
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China.,Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Xiaoxu Sun
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China.,Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Rui Xu
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China.,Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Fuqing Xu
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China.,Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Weimin Sun
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China.,Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
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Xu J, Yu T, Zois CE, Cheng JX, Tang Y, Harris AL, Huang WE. Unveiling Cancer Metabolism through Spontaneous and Coherent Raman Spectroscopy and Stable Isotope Probing. Cancers (Basel) 2021; 13:1718. [PMID: 33916413 PMCID: PMC8038603 DOI: 10.3390/cancers13071718] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 03/24/2021] [Accepted: 03/28/2021] [Indexed: 11/25/2022] Open
Abstract
Metabolic reprogramming is a common hallmark in cancer. The high complexity and heterogeneity in cancer render it challenging for scientists to study cancer metabolism. Despite the recent advances in single-cell metabolomics based on mass spectrometry, the analysis of metabolites is still a destructive process, thus limiting in vivo investigations. Being label-free and nonperturbative, Raman spectroscopy offers intrinsic information for elucidating active biochemical processes at subcellular level. This review summarizes recent applications of Raman-based techniques, including spontaneous Raman spectroscopy and imaging, coherent Raman imaging, and Raman-stable isotope probing, in contribution to the molecular understanding of the complex biological processes in the disease. In addition, this review discusses possible future directions of Raman-based technologies in cancer research.
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Affiliation(s)
- Jiabao Xu
- Department of Engineering Science, University of Oxford, Oxford OX1 3PJ, UK;
| | - Tong Yu
- Department of Engineering Science, University of Oxford, Oxford OX1 3PJ, UK;
| | - Christos E. Zois
- Molecular Oncology Laboratories, Department of Oncology, Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, Oxford University, Oxford OX3 9DS, UK;
- Department of Radiotherapy and Oncology, School of Health, Democritus University of Thrace, 68100 Alexandroupolis, Greece
| | - Ji-Xin Cheng
- Department of Biomedical Engineering, Boston University, Boston, MS 02215, USA;
| | - Yuguo Tang
- Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou 215163, China;
| | - Adrian L. Harris
- Molecular Oncology Laboratories, Department of Oncology, Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, Oxford University, Oxford OX3 9DS, UK;
| | - Wei E. Huang
- Department of Engineering Science, University of Oxford, Oxford OX1 3PJ, UK;
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Kaupper T, Mendes LW, Harnisz M, Krause SMB, Horn MA, Ho A. Recovery in methanotrophic activity does not reflect on the methane-driven interaction network after peat mining. Appl Environ Microbiol 2021; 87:AEM. [PMID: 33355115 DOI: 10.1128/AEM.02355-20] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Aerobic methanotrophs are crucial in ombrotrophic peatlands, driving the methane and nitrogen cycles. Peat mining adversely affects the methanotrophs, but activity and community composition/abundances may recover after restoration. Considering that the methanotrophic activity and growth are significantly stimulated in the presence of other microorganisms, the methane-driven interaction network, encompassing methanotrophs and non-methanotrophs (i.e., methanotrophic interactome), may also be relevant in conferring community resilience. Yet, little is known of the response and recovery of the methanotrophic interactome to disturbances. Here, we determined the recovery of the methanotrophic interactome as inferred by a co-occurrence network analysis, comparing a pristine and restored peatland. We coupled a DNA-based stable isotope probing (SIP) approach using 13C-CH4 to a co-occurrence network analysis derived from the 13C-enriched 16S rRNA gene sequences to relate the response in methanotrophic activity to the structuring of the interaction network. Methanotrophic activity and abundances recovered after peat restoration since 2000. 'Methylomonaceae' was the predominantly active methanotrophs in both peatlands, but differed in the relative abundance of Methylacidiphilaceae and Methylocystis However, bacterial community composition was distinct in both peatlands. Likewise, the methanotrophic interactome was profoundly altered in the restored peatland. Structuring of the interaction network after peat mining resulted in the loss of complexity and modularity, indicating a less connected and efficient network, which may have consequences in the event of recurring/future disturbances. Therefore, determining the response of the methane-driven interaction network, in addition to relating methanotrophic activity to community composition/abundances, provided a more comprehensive understanding of the resilience of the methanotrophs.Importance The resilience and recovery of microorganisms from disturbances are often determined with regard to their activity and community composition/abundances. Rarely has the response of the network of interacting microorganisms been considered, despite accumulating evidence showing that microbial interaction modulates community functioning. Comparing the methane-driven interaction network of a pristine and restored peatland, our findings revealed that the metabolically active microorganisms were less connected and formed less modular 'hubs' in the restored peatland, indicative of a less complex network which may have consequences with recurring disturbances and environmental changes. This also suggests that the resilience and full recovery in the methanotrophic activity and abundances do not reflect on the interaction network. Therefore, it is relevant to consider the interaction-induced response, in addition to documenting changes in activity and community composition/abundances, to provide a comprehensive understanding of the resilience of microorganisms to disturbances.
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Geerlings NMJ, Geelhoed JS, Vasquez-Cardenas D, Kienhuis MVM, Hidalgo-Martinez S, Boschker HTS, Middelburg JJ, Meysman FJR, Polerecky L. Cell Cycle, Filament Growth and Synchronized Cell Division in Multicellular Cable Bacteria. Front Microbiol 2021; 12:620807. [PMID: 33584623 PMCID: PMC7873302 DOI: 10.3389/fmicb.2021.620807] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 01/06/2021] [Indexed: 11/13/2022] Open
Abstract
Cable bacteria are multicellular, Gram-negative filamentous bacteria that display a unique division of metabolic labor between cells. Cells in deeper sediment layers are oxidizing sulfide, while cells in the surface layers of the sediment are reducing oxygen. The electrical coupling of these two redox half reactions is ensured via long-distance electron transport through a network of conductive fibers that run in the shared cell envelope of the centimeter-long filament. Here we investigate how this unique electrogenic metabolism is linked to filament growth and cell division. Combining dual-label stable isotope probing (13C and 15N), nanoscale secondary ion mass spectrometry, fluorescence microscopy and genome analysis, we find that the cell cycle of cable bacteria cells is highly comparable to that of other, single-celled Gram-negative bacteria. However, the timing of cell growth and division appears to be tightly and uniquely controlled by long-distance electron transport, as cell division within an individual filament shows a remarkable synchronicity that extends over a millimeter length scale. To explain this, we propose the "oxygen pacemaker" model in which a filament only grows when performing long-distance transport, and the latter is only possible when a filament has access to oxygen so it can discharge electrons from its internal electrical network.
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Affiliation(s)
| | | | | | | | | | | | | | - Filip J. R. Meysman
- Department of Biology, University of Antwerp, Antwerp, Belgium
- Department of Biotechnology, Delft University of Technology, Delft, Netherlands
| | - Lubos Polerecky
- Department of Earth Sciences, Utrecht University, Utrecht, Netherlands
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40
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Wilhelm RC, Pepe-Ranney C, Weisenhorn P, Lipton M, Buckley DH. Competitive Exclusion and Metabolic Dependency among Microorganisms Structure the Cellulose Economy of an Agricultural Soil. mBio 2021; 12:e03099-20. [PMID: 33402535 DOI: 10.1128/mBio.03099-20] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Microorganisms that degrade cellulose utilize extracellular reactions that yield free by-products which can promote interactions with noncellulolytic organisms. We hypothesized that these interactions determine the ecological and physiological traits governing the fate of cellulosic carbon (C) in soil. We performed comparative genomics with genome bins from a shotgun metagenomic-stable isotope probing experiment to characterize the attributes of cellulolytic and noncellulolytic taxa accessing 13C from cellulose. We hypothesized that cellulolytic taxa would exhibit competitive traits that limit access, while noncellulolytic taxa would display greater metabolic dependency, such as signatures of adaptive gene loss. We tested our hypotheses by evaluating genomic traits indicative of competitive exclusion or metabolic dependency, such as antibiotic production, growth rate, surface attachment, biomass degrading potential, and auxotrophy. The most 13C-enriched taxa were cellulolytic Cellvibrio (Gammaproteobacteria) and Chaetomium (Ascomycota), which exhibited a strategy of self-sufficiency (prototrophy), rapid growth, and competitive exclusion via antibiotic production. Auxotrophy was more prevalent in cellulolytic Actinobacteria than in cellulolytic Proteobacteria, demonstrating differences in dependency among cellulose degraders. Noncellulolytic taxa that accessed 13C from cellulose (Planctomycetales, Verrucomicrobia, and Vampirovibrionales) were also more dependent, as indicated by patterns of auxotrophy and 13C labeling (i.e., partial labeling or labeling at later stages). Major 13C-labeled cellulolytic microbes (e.g., Sorangium, Actinomycetales, Rhizobiales, and Caulobacteraceae) possessed adaptations for surface colonization (e.g., gliding motility, hyphae, attachment structures) signifying the importance of surface ecology in decomposing particulate organic matter. Our results demonstrated that access to cellulosic C was accompanied by ecological trade-offs characterized by differing degrees of metabolic dependency and competitive exclusion.
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41
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Liu S, Baetge N, Comstock J, Opalk K, Parsons R, Halewood E, English CJ, Giovannoni S, Bolaños LM, Nelson CE, Vergin K, Carlson CA. Stable Isotope Probing Identifies Bacterioplankton Lineages Capable of Utilizing Dissolved Organic Matter Across a Range of Bioavailability. Front Microbiol 2020; 11:580397. [PMID: 33117322 PMCID: PMC7575717 DOI: 10.3389/fmicb.2020.580397] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 09/03/2020] [Indexed: 01/04/2023] Open
Abstract
Bacterioplankton consume about half of the dissolved organic matter (DOM) produced by phytoplankton. DOM released from phytoplankton consists of a myriad of compounds that span a range of biological reactivity from labile to recalcitrant. Linking specific bacterioplankton lineages to the incorporation of DOM compounds into biomass is important to understand microbial niche partitioning. We conducted a series of DNA-stable isotope probing (SIP) experiments using 13C-labeled substrates of varying lability including amino acids, cyanobacteria lysate, and DOM from diatom and cyanobacteria isolates concentrated on solid phase extraction PPL columns (SPE-DOM). Amendments of substrates into Sargasso Sea bacterioplankton communities were conducted to explore microbial response and DNA-SIP was used to determine which lineages of Bacteria and Archaea were responsible for uptake and incorporation. Greater increases in bacterioplankton abundance and DOC removal were observed in incubations amended with cyanobacteria-derived lysate and amino acids compared to the SPE-DOM, suggesting that the latter retained proportionally more recalcitrant DOM compounds. DOM across a range of bioavailability was utilized by diverse prokaryotic taxa with copiotrophs becoming the most abundant 13C-incorporating taxa in the amino acid treatment and oligotrophs becoming the most abundant 13C-incorporating taxa in SPE-DOM treatments. The lineages that responded to SPE-DOM amendments were also prevalent in the mesopelagic of the Sargasso Sea, suggesting that PPL extraction of phytoplankton-derived DOM isolates compounds of ecological relevance to oligotrophic heterotrophic bacterioplankton. Our study indicates that DOM quality is an important factor controlling the diversity of the microbial community response, providing insights into the roles of different bacterioplankton in resource exploitation and efficiency of marine carbon cycling.
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Affiliation(s)
- Shuting Liu
- Department of Ecology, Evolution, and Marine Biology, Marine Science Institute, University of California, Santa Barbara, Santa Barbara, CA, United States
| | - Nicholas Baetge
- Department of Ecology, Evolution, and Marine Biology, Marine Science Institute, University of California, Santa Barbara, Santa Barbara, CA, United States
| | - Jacqueline Comstock
- Department of Ecology, Evolution, and Marine Biology, Marine Science Institute, University of California, Santa Barbara, Santa Barbara, CA, United States
| | - Keri Opalk
- Department of Ecology, Evolution, and Marine Biology, Marine Science Institute, University of California, Santa Barbara, Santa Barbara, CA, United States
| | - Rachel Parsons
- Bermuda Institute of Ocean Sciences, Saint George, Bermuda
| | - Elisa Halewood
- Department of Ecology, Evolution, and Marine Biology, Marine Science Institute, University of California, Santa Barbara, Santa Barbara, CA, United States
| | - Chance J English
- Department of Ecology, Evolution, and Marine Biology, Marine Science Institute, University of California, Santa Barbara, Santa Barbara, CA, United States
| | - Stephen Giovannoni
- Department of Microbiology, Oregon State University, Corvallis, OR, United States
| | - Luis M Bolaños
- Department of Microbiology, Oregon State University, Corvallis, OR, United States
| | - Craig E Nelson
- Daniel K. Inouye Center for Microbial Oceanography: Research and Education, Department of Oceanography and Hawai'i Sea Grant, School of Ocean and Earth Science and Technology, University of Hawai'i at Mānoa, Honolulu, HI, United States
| | - Kevin Vergin
- Microbial DNA Analytics, Phoenix, OR, United States
| | - Craig A Carlson
- Department of Ecology, Evolution, and Marine Biology, Marine Science Institute, University of California, Santa Barbara, Santa Barbara, CA, United States
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McBride SG, Choudoir M, Fierer N, Strickland MS. Volatile organic compounds from leaf litter decomposition alter soil microbial communities and carbon dynamics. Ecology 2020; 101:e03130. [PMID: 32621285 DOI: 10.1002/ecy.3130] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 03/25/2020] [Accepted: 05/05/2020] [Indexed: 01/09/2023]
Abstract
Investigations into the transfer of carbon from plant litter to underlying soil horizons have primarily focused on the leaching of soluble carbon from litter belowground or the mixing of litter directly into soil. However, previous work has largely ignored the role of volatile organic compounds (VOCs) released during litter decomposition. Unlike most leaf carbon, these litter-derived VOCs are able to diffuse directly into the soil matrix. Here, we used a 99-d microcosm experiment to track VOCs produced during microbial decomposition of 13 C-labeled leaf litter into soil carbon fractions where the decomposing litters were only sharing headspace with the soil samples, thus preventing direct contact and aqueous movement of litter carbon. We also determined the effects of these litter-derived VOCs on soil microbial community structure. We demonstrated that the litter VOCs contributed to all measured soil carbon pools. Specifically, VOC-derived carbon accounted for 2.0, 0.61, 0.18, and 0.08% of carbon in the microbial biomass, dissolved organic matter, mineral-associated organic matter, and particulate organic matter pools, respectively. We also show that litter-derived VOCs can affect soil bacterial and fungal community diversity and composition. These findings highlight the importance of an underappreciated pathway where VOCs alter soil microbial communities and carbon dynamics.
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Affiliation(s)
- Steven G McBride
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia, 24061, USA
| | - Mallory Choudoir
- Cooperative Institute for Research in Environmental Studies (CIRES), University of Colorado Boulder, Boulder, Colorado, 80309, USA
| | - Noah Fierer
- Cooperative Institute for Research in Environmental Studies (CIRES), University of Colorado Boulder, Boulder, Colorado, 80309, USA.,Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Colorado, 80309, USA
| | - Michael S Strickland
- Department of Soil and Water Systems, University of Idaho, Moscow, Idaho, 83844, USA
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Zhu B, Friedrich S, Wang Z, Táncsics A, Lueders T. Availability of Nitrite and Nitrate as Electron Acceptors Modulates Anaerobic Toluene-Degrading Communities in Aquifer Sediments. Front Microbiol 2020; 11:1867. [PMID: 32922372 PMCID: PMC7456981 DOI: 10.3389/fmicb.2020.01867] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 07/16/2020] [Indexed: 01/04/2023] Open
Abstract
Microorganisms are essential in the degradation of environmental pollutants. Aromatic hydrocarbons, e.g., benzene, toluene, ethylbenzene, and xylene (BTEX), are common aquifer contaminants, whose degradation in situ is often limited by the availability of electron acceptors. It is clear that different electron acceptors such as nitrate, iron, or sulfate support the activity of distinct degraders. However, this has not been demonstrated for the availability of nitrate vs. nitrite, both of which can be respired in reductive nitrogen cycling. Here via DNA-stable isotope probing, we report that nitrate and nitrite provided as electron acceptors in different concentrations and ratios not only modulated the microbial communities responsible for toluene degradation but also influenced how nitrate reduction proceeded. Zoogloeaceae members, mainly Azoarcus spp., were the key toluene degraders with nitrate-only, or both nitrate and nitrite as electron acceptors. In addition, a shift within Azoarcus degrader populations was observed on the amplicon sequence variant (ASV) level depending on electron acceptor ratios. In contrast, members of the Sphingomonadales were likely the most active toluene degraders when only nitrite was provided. Nitrate reduction did not proceed beyond nitrite in the nitrate-only treatment, while it continued when nitrite was initially also present in the microcosms. Likely, this was attributed to the fact that different microbial communities were stimulated and active in different microcosms. Together, these findings demonstrate that the availability of nitrate and nitrite can define degrader community selection and N-reduction outcomes. It also implies that nitrate usage efficiency in bioremediation could possibly be enhanced by an initial co-supply of nitrite, via modulating the active degrader communities.
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Affiliation(s)
- Baoli Zhu
- Chair of Ecological Microbiology, University of Bayreuth, Bayreuth, Germany
| | | | - Zhe Wang
- Chair of Ecological Microbiology, University of Bayreuth, Bayreuth, Germany
| | - András Táncsics
- Regional University Center of Excellence in Environmental Industry, Szent Istvan University, Gödöllö, Hungary
| | - Tillmann Lueders
- Chair of Ecological Microbiology, University of Bayreuth, Bayreuth, Germany
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44
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Sieradzki ET, Koch BJ, Greenlon A, Sachdeva R, Malmstrom RR, Mau RL, Blazewicz SJ, Firestone MK, Hofmockel KS, Schwartz E, Hungate BA, Pett-Ridge J. Measurement Error and Resolution in Quantitative Stable Isotope Probing: Implications for Experimental Design. mSystems 2020; 5:e00151-20. [PMID: 32694124 PMCID: PMC7566279 DOI: 10.1128/msystems.00151-20] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 06/29/2020] [Indexed: 12/14/2022] Open
Abstract
Quantitative stable isotope probing (qSIP) estimates isotope tracer incorporation into DNA of individual microbes and can link microbial biodiversity and biogeochemistry in complex communities. As with any quantitative estimation technique, qSIP involves measurement error, and a fuller understanding of error, precision, and statistical power benefits qSIP experimental design and data interpretation. We used several qSIP data sets-from soil and seawater microbiomes-to evaluate how variance in isotope incorporation estimates depends on organism abundance and resolution of the density fractionation scheme. We assessed statistical power for replicated qSIP studies, plus sensitivity and specificity for unreplicated designs. As a taxon's abundance increases, the variance of its weighted mean density declines. Nine fractions appear to be a reasonable trade-off between cost and precision for most qSIP applications. Increasing the number of density fractions beyond that reduces variance, although the magnitude of this benefit declines with additional fractions. Our analysis suggests that, if a taxon has an isotope enrichment of 10 atom% excess, there is a 60% chance that this will be detected as significantly different from zero (with alpha 0.1). With five replicates, isotope enrichment of 5 atom% could be detected with power (0.6) and alpha (0.1). Finally, we illustrate the importance of internal standards, which can help to calibrate per sample conversions of %GC to mean weighted density. These results should benefit researchers designing future SIP experiments and provide a useful reference for metagenomic SIP applications where both financial and computational limitations constrain experimental scope.IMPORTANCE One of the biggest challenges in microbial ecology is correlating the identity of microorganisms with the roles they fulfill in natural environmental systems. Studies of microbes in pure culture reveal much about their genomic content and potential functions but may not reflect an organism's activity within its natural community. Culture-independent studies supply a community-wide view of composition and function in the context of community interactions but often fail to link the two. Quantitative stable isotope probing (qSIP) is a method that can link the identity and functional activity of specific microbes within a naturally occurring community. Here, we explore how the resolution of density gradient fractionation affects the error and precision of qSIP results, how they may be improved via additional experimental replication, and discuss cost-benefit balanced scenarios for SIP experimental design.
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Affiliation(s)
- Ella T Sieradzki
- University of California Berkeley, Environmental Science and Policy Management, Berkeley, California, USA
| | - Benjamin J Koch
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
- Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona, USA
| | - Alex Greenlon
- University of California Berkeley, Environmental Science and Policy Management, Berkeley, California, USA
| | - Rohan Sachdeva
- University of California Berkeley, Earth and Planetary Sciences, Berkeley, California, USA
| | - Rex R Malmstrom
- Department of Energy Joint Genome Institute, Berkeley, California, USA
| | - Rebecca L Mau
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
| | - Steven J Blazewicz
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California, USA
| | - Mary K Firestone
- University of California Berkeley, Environmental Science and Policy Management, Berkeley, California, USA
| | - Kirsten S Hofmockel
- Pacific Northwest National Laboratory, Richland, Washington, USA
- Department of Ecology, Evolution and Organismal Biology, Iowa State University, Ames, Iowa, USA
| | - Egbert Schwartz
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
- Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona, USA
| | - Bruce A Hungate
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, Arizona, USA
- Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona, USA
| | - Jennifer Pett-Ridge
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California, USA
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45
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Abstract
The climate-active gas isoprene is the major volatile produced by a variety of trees and is released into the atmosphere in enormous quantities, on a par with global emissions of methane. While isoprene production in plants and its effect on atmospheric chemistry have received considerable attention, research into the biological isoprene sink has been neglected until recently. Here, we review current knowledge on the sources and sinks of isoprene and outline its environmental effects. Focusing on degradation by microbes, many of which are able to use isoprene as the sole source of carbon and energy, we review recent studies characterizing novel isoprene degraders isolated from soils, marine sediments and in association with plants. We describe the development and use of molecular methods to identify, quantify and genetically characterize isoprene-degrading strains in environmental samples. Finally, this review identifies research imperatives for the further study of the environmental impact, ecology, regulation and biochemistry of this interesting group of microbes.
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Affiliation(s)
- J Colin Murrell
- School of Environmental Sciences, University of East Anglia, Norwich, NR4 7TJ, UK
| | - Terry J McGenity
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, UK
| | - Andrew T Crombie
- School of Biological Sciences, University of East Anglia, Norwich, NR4 7TJ, UK
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46
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Steinke L, Slysz GW, Lipton MS, Klatt C, Moran JJ, Romine MF, Wood JM, Anderson G, Bryant DA, Ward DM. Short-Term Stable Isotope Probing of Proteins Reveals Taxa Incorporating Inorganic Carbon in a Hot Spring Microbial Mat. Appl Environ Microbiol 2020; 86:e01829-19. [PMID: 31953342 DOI: 10.1128/AEM.01829-19] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Accepted: 01/12/2020] [Indexed: 11/20/2022] Open
Abstract
The upper green layer of the chlorophototrophic microbial mats associated with the alkaline siliceous hot springs of Yellowstone National Park consists of oxygenic cyanobacteria (Synechococcus spp.), anoxygenic Roseiflexus spp., and several other anoxygenic chlorophototrophs. Synechococcus spp. are believed to be the main fixers of inorganic carbon (Ci), but some evidence suggests that Roseiflexus spp. also contribute to inorganic carbon fixation during low-light, anoxic morning periods. Contributions of other phototrophic taxa have not been investigated. In order to follow the pathway of Ci incorporation into different taxa, mat samples were incubated with [13C]bicarbonate for 3 h during the early-morning, low-light anoxic period. Extracted proteins were treated with trypsin and analyzed by mass spectrometry, leading to peptide identifications and peptide isotopic profile signatures containing evidence of 13C label incorporation. A total of 25,483 peptides, corresponding to 7,221 proteins, were identified from spectral features and associated with mat taxa by comparison to metagenomic assembly sequences. A total of 1,417 peptides, derived from 720 proteins, were detectably labeled with 13C. Most 13C-labeled peptides were derived from proteins of Synechococcus spp. and Roseiflexus spp. Chaperones and proteins of carbohydrate metabolism were most abundantly labeled. Proteins involved in photosynthesis, Ci fixation, and N2 fixation were also labeled in Synechococcus spp. Importantly, most proteins of the 3-hydroxypropionate bi-cycle for Ci fixation in Roseiflexus spp. were labeled, establishing that members of this taxocene contribute to Ci fixation. Other taxa showed much lower [13C]bicarbonate incorporation.IMPORTANCE Yellowstone hot spring mats have been studied as natural models for understanding microbial community ecology and as modern analogs of stromatolites, the earliest community fossils on Earth. Stable-isotope probing of proteins (Pro-SIP) permitted short-term interrogation of the taxa that are involved in the important process of light-driven Ci fixation in this highly active community and will be useful in linking other metabolic processes to mat taxa. Here, evidence is presented that Roseiflexus spp., which use the 3-hydroxypropionate bi-cycle, are active in Ci fixation. Because this pathway imparts a lower degree of selection of isotopically heavy Ci than does the Calvin-Benson-Bassham cycle, the results suggest a mechanism to explain why the natural abundance of 13C in mat biomass is greater than expected if only the latter pathway were involved. Understanding how mat community members influence the 13C/12C ratios of mat biomass will help geochemists interpret the 13C/12C ratios of organic carbon in the fossil record.
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47
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Weis S, Schnell S, Egert M. Towards safer stable isotope probing - effect of formamide on the separation of isotope-labeled and unlabeled Escherichia coli RNA by isopycnic density ultracentrifugation. Can J Microbiol 2020; 66:491-494. [PMID: 32134703 DOI: 10.1139/cjm-2019-0612] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
RNA-based stable isotope probing (RNA-SIP) is used in molecular microbial ecology to link the identity of microorganisms in a complex community with the assimilation of a distinct substrate. The technique is highly dependent on a reliable separation of isotopic-labeled RNA from unlabeled RNA by isopycnic density gradient ultracentrifugation. Here we show that 13C-labeled and unlabeled Escherichia coli RNA can be sufficiently separated by isopycnic ultracentrifugation even in the absence of formamide. However, a slightly lower starting density is needed to obtain a distribution pattern similar to that obtained when formamide was used. Hence, the commonly used addition of formamide to the centrifugation solution might not be needed to separate 13C-labeled RNA from unlabeled RNA, but this must be verified for more complex environmental mixtures of RNA. Clearly, an omission of formamide would increase the safety of RNA-SIP analyses.
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Affiliation(s)
- Severin Weis
- Faculty of Medical and Life Sciences, Institute of Precision Medicine, Microbiology and Hygiene Group, Furtwangen University, Villingen-Schwenningen, Germany
| | - Sylvia Schnell
- Institute of Applied Microbiology, Research Center for BioSystems, Land Use, and Nutrition (IFZ), Justus-Liebig-University Giessen, Germany
| | - Markus Egert
- Faculty of Medical and Life Sciences, Institute of Precision Medicine, Microbiology and Hygiene Group, Furtwangen University, Villingen-Schwenningen, Germany
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48
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Geerlings NMJ, Karman C, Trashin S, As KS, Kienhuis MVM, Hidalgo-Martinez S, Vasquez-Cardenas D, Boschker HTS, De Wael K, Middelburg JJ, Polerecky L, Meysman FJR. Division of labor and growth during electrical cooperation in multicellular cable bacteria. Proc Natl Acad Sci U S A 2020; 117:5478-85. [PMID: 32094191 DOI: 10.1073/pnas.1916244117] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Cable bacteria form centimeter-long, multicellular filaments whose energy metabolism involves cooperation among cells that separately perform oxidation of the electron donor and reduction of the electron acceptor. This cooperative division of labor is facilitated via long-range electrical currents that run from cell to cell along a network of conductive fibers. Here we show that biomass synthesis shows a surprising asymmetry along the filament: only the cells oxidizing the electron donor conserve energy for growth, while the other cells reduce electron acceptors without biosynthesis. Our study hence provides insights into the physiology of an unconventional chemolithotroph, which forms a multicellular electrically connected system with unique functional differentiation, integration, and coordination. Multicellularity is a key evolutionary innovation, leading to coordinated activity and resource sharing among cells, which generally occurs via the physical exchange of chemical compounds. However, filamentous cable bacteria display a unique metabolism in which redox transformations in distant cells are coupled via long-distance electron transport rather than an exchange of chemicals. This challenges our understanding of organismal functioning, as the link among electron transfer, metabolism, energy conservation, and filament growth in cable bacteria remains enigmatic. Here, we show that cells within individual filaments of cable bacteria display a remarkable dichotomy in biosynthesis that coincides with redox zonation. Nanoscale secondary ion mass spectrometry combined with 13C (bicarbonate and propionate) and 15N-ammonia isotope labeling reveals that cells performing sulfide oxidation in deeper anoxic horizons have a high assimilation rate, whereas cells performing oxygen reduction in the oxic zone show very little or no label uptake. Accordingly, oxygen reduction appears to merely function as a mechanism to quickly dispense of electrons with little to no energy conservation, while biosynthesis and growth are restricted to sulfide-respiring cells. Still, cells can immediately switch roles when redox conditions change, and show no differentiation, which suggests that the “community service” performed by the cells in the oxic zone is only temporary. Overall, our data reveal a division of labor and electrical cooperation among cells that has not been seen previously in multicellular organisms.
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49
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Abstract
In our recent work, we developed an optofluidic platform that allows a direct link to be made between the phenotypes (functions) and the genotypes (genes) of microbial cells within natural communities. By combining stable isotope probing, optical tweezers, Raman microspectroscopy, and microfluidics, the platform performs automated Raman-based sorting of taxa from within a complex community in terms of their functional properties. In comparison with manual sorting approaches, our method provides high throughput (up to 500 cells per hour) and very high sorting accuracy (98.3 ± 1.7%), and significantly reduces the human labour required. The system provides an efficient manner to untangle the contributions of individual members within environmental and host-associated microbiomes. In this News and Thoughts, we provide an overview of our platform, describe potential applications, suggest ways in which the system could be improved, and discuss future directions in which Raman-based analysis of microbial populations might be developed.
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Affiliation(s)
- Kang Soo Lee
- Institute for Environmental Engineering, Department of Civil, Environmental and Geomatic Engineering, ETH Zurich, Zurich, Switzerland
| | - Michael Wagner
- University of Vienna, Centre for Microbiology and Environmental Systems Science, Department of Microbiology and Ecosystem Science, Althanstrasse 14, 1090 Vienna, Austria.,Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, 9220 Aalborg, Denmark
| | - Roman Stocker
- Institute for Environmental Engineering, Department of Civil, Environmental and Geomatic Engineering, ETH Zurich, Zurich, Switzerland
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50
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Aromokeye DA, Kulkarni AC, Elvert M, Wegener G, Henkel S, Coffinet S, Eickhorst T, Oni OE, Richter-Heitmann T, Schnakenberg A, Taubner H, Wunder L, Yin X, Zhu Q, Hinrichs KU, Kasten S, Friedrich MW. Rates and Microbial Players of Iron-Driven Anaerobic Oxidation of Methane in Methanic Marine Sediments. Front Microbiol 2020; 10:3041. [PMID: 32010098 PMCID: PMC6979488 DOI: 10.3389/fmicb.2019.03041] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Accepted: 12/17/2019] [Indexed: 11/15/2022] Open
Abstract
The flux of methane, a potent greenhouse gas, from the seabed is largely controlled by anaerobic oxidation of methane (AOM) coupled to sulfate reduction (S-AOM) in the sulfate methane transition (SMT). S-AOM is estimated to oxidize 90% of the methane produced in marine sediments and is mediated by a consortium of anaerobic methanotrophic archaea (ANME) and sulfate reducing bacteria. An additional methane sink, i.e., iron oxide coupled AOM (Fe-AOM), has been suggested to be active in the methanic zone of marine sediments. Geochemical signatures below the SMT such as high dissolved iron, low to undetectable sulfate and high methane concentrations, together with the presence of iron oxides are taken as prerequisites for this process. So far, Fe-AOM has neither been proven in marine sediments nor have the governing key microorganisms been identified. Here, using a multidisciplinary approach, we show that Fe-AOM occurs in iron oxide-rich methanic sediments of the Helgoland Mud Area (North Sea). When sulfate reduction was inhibited, different iron oxides facilitated AOM in long-term sediment slurry incubations but manganese oxide did not. Especially magnetite triggered substantial Fe-AOM activity and caused an enrichment of ANME-2a archaea. Methane oxidation rates of 0.095 ± 0.03 nmol cm-3 d-1 attributable to Fe-AOM were obtained in short-term radiotracer experiments. The decoupling of AOM from sulfate reduction in the methanic zone further corroborated that AOM was iron oxide-driven below the SMT. Thus, our findings prove that Fe-AOM occurs in methanic marine sediments containing mineral-bound ferric iron and is a previously overlooked but likely important component in the global methane budget. This process has the potential to sustain microbial life in the deep biosphere.
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Affiliation(s)
- David A. Aromokeye
- Microbial Ecophysiology Group, Faculty of Biology/Chemistry, University of Bremen, Bremen, Germany
- MARUM – Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | - Ajinkya C. Kulkarni
- Microbial Ecophysiology Group, Faculty of Biology/Chemistry, University of Bremen, Bremen, Germany
- MARUM – Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
- International Max Planck Research School of Marine Microbiology, Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Marcus Elvert
- MARUM – Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
- Faculty of Geosciences, University of Bremen, Bremen, Germany
| | - Gunter Wegener
- MARUM – Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
- Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Susann Henkel
- MARUM – Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
- Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
| | - Sarah Coffinet
- MARUM – Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | - Thilo Eickhorst
- Faculty of Biology/Chemistry, University of Bremen, Bremen, Germany
| | - Oluwatobi E. Oni
- Microbial Ecophysiology Group, Faculty of Biology/Chemistry, University of Bremen, Bremen, Germany
| | - Tim Richter-Heitmann
- Microbial Ecophysiology Group, Faculty of Biology/Chemistry, University of Bremen, Bremen, Germany
| | - Annika Schnakenberg
- Microbial Ecophysiology Group, Faculty of Biology/Chemistry, University of Bremen, Bremen, Germany
- MARUM – Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
- International Max Planck Research School of Marine Microbiology, Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Heidi Taubner
- MARUM – Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
- Faculty of Geosciences, University of Bremen, Bremen, Germany
| | - Lea Wunder
- Microbial Ecophysiology Group, Faculty of Biology/Chemistry, University of Bremen, Bremen, Germany
| | - Xiuran Yin
- Microbial Ecophysiology Group, Faculty of Biology/Chemistry, University of Bremen, Bremen, Germany
- MARUM – Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | - Qingzeng Zhu
- MARUM – Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | - Kai-Uwe Hinrichs
- MARUM – Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
- Faculty of Geosciences, University of Bremen, Bremen, Germany
| | - Sabine Kasten
- MARUM – Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
- Faculty of Geosciences, University of Bremen, Bremen, Germany
- Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
| | - Michael W. Friedrich
- Microbial Ecophysiology Group, Faculty of Biology/Chemistry, University of Bremen, Bremen, Germany
- MARUM – Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
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