1
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Dalcin Martins P, de Monlevad JPC, Echeveste Medrano MJ, Lenstra WK, Wallenius AJ, Hermans M, Slomp CP, Welte CU, Jetten MSM, van Helmond NAGM. Sulfide Toxicity as Key Control on Anaerobic Oxidation of Methane in Eutrophic Coastal Sediments. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:11421-11435. [PMID: 38888209 PMCID: PMC11223495 DOI: 10.1021/acs.est.3c10418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 06/07/2024] [Accepted: 06/10/2024] [Indexed: 06/20/2024]
Abstract
Coastal zones account for 75% of marine methane emissions, despite covering only 15% of the ocean surface area. In these ecosystems, the tight balance between methane production and oxidation in sediments prevents most methane from escaping into seawater. However, anthropogenic activities could disrupt this balance, leading to an increased methane escape from coastal sediments. To quantify and unravel potential mechanisms underlying this disruption, we used a suite of biogeochemical and microbiological analyses to investigate the impact of anthropogenically induced redox shifts on methane cycling in sediments from three sites with contrasting bottom water redox conditions (oxic-hypoxic-euxinic) in the eutrophic Stockholm Archipelago. Our results indicate that the methane production potential increased under hypoxia and euxinia, while anaerobic oxidation of methane was disrupted under euxinia. Experimental, genomic, and biogeochemical data suggest that the virtual disappearance of methane-oxidizing archaea at the euxinic site occurred due to sulfide toxicity. This could explain a near 7-fold increase in the extent of escape of benthic methane at the euxinic site relative to the hypoxic one. In conclusion, these insights reveal how the development of euxinia could disrupt the coastal methane biofilter, potentially leading to increased methane emissions from coastal zones.
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Affiliation(s)
- Paula Dalcin Martins
- Department
of Microbiology, Radboud Institute for Biological and Environmental
Sciences, Radboud University, Nijmegen 6525 AJ, The Netherlands
- Department
of Ecosystem and Landscape Dynamics, Institute for Biodiversity and
Ecosystem Dynamics (IBED), University of
Amsterdam, Amsterdam 1098 XH, The Netherlands
| | - João P.
R. C. de Monlevad
- Department
of Microbiology, Radboud Institute for Biological and Environmental
Sciences, Radboud University, Nijmegen 6525 AJ, The Netherlands
| | - Maider J. Echeveste Medrano
- Department
of Microbiology, Radboud Institute for Biological and Environmental
Sciences, Radboud University, Nijmegen 6525 AJ, The Netherlands
| | - Wytze Klaas Lenstra
- Department
of Microbiology, Radboud Institute for Biological and Environmental
Sciences, Radboud University, Nijmegen 6525 AJ, The Netherlands
- Department
of Earth Sciences—Geochemistry, Utrecht
University, Utrecht 3584 CB, The Netherlands
| | - Anna Julia Wallenius
- Department
of Microbiology, Radboud Institute for Biological and Environmental
Sciences, Radboud University, Nijmegen 6525 AJ, The Netherlands
| | - Martijn Hermans
- Department
of Earth Sciences—Geochemistry, Utrecht
University, Utrecht 3584 CB, The Netherlands
- Baltic
Sea Centre, Stockholm University, Stockholm 114 18, Sweden
| | - Caroline P. Slomp
- Department
of Microbiology, Radboud Institute for Biological and Environmental
Sciences, Radboud University, Nijmegen 6525 AJ, The Netherlands
- Department
of Earth Sciences—Geochemistry, Utrecht
University, Utrecht 3584 CB, The Netherlands
| | - Cornelia Ulrike Welte
- Department
of Microbiology, Radboud Institute for Biological and Environmental
Sciences, Radboud University, Nijmegen 6525 AJ, The Netherlands
| | - Mike S. M. Jetten
- Department
of Microbiology, Radboud Institute for Biological and Environmental
Sciences, Radboud University, Nijmegen 6525 AJ, The Netherlands
| | - Niels A. G. M. van Helmond
- Department
of Microbiology, Radboud Institute for Biological and Environmental
Sciences, Radboud University, Nijmegen 6525 AJ, The Netherlands
- Department
of Earth Sciences—Geochemistry, Utrecht
University, Utrecht 3584 CB, The Netherlands
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Carmichael MJ, Martinez M, Bräuer SL, Ardón M. Microbial Communities in Standing Dead Trees in Ghost Forests are Largely Aerobic, Saprophytic, and Methanotrophic. Curr Microbiol 2024; 81:229. [PMID: 38896154 PMCID: PMC11186919 DOI: 10.1007/s00284-024-03767-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2024] [Accepted: 06/04/2024] [Indexed: 06/21/2024]
Abstract
Standing dead trees (snags) are recognized for their influence on methane (CH4) cycling in coastal wetlands, yet the biogeochemical processes that control the magnitude and direction of fluxes across the snag-atmosphere interface are not fully elucidated. Herein, we analyzed microbial communities and fluxes at one height from ten snags in a ghost forest wetland. Snag-atmosphere CH4 fluxes were highly variable (- 0.11-0.51 mg CH4 m-2 h-1). CH4 production was measured in three out of ten snags; whereas, CH4 consumption was measured in two out of ten snags. Potential CH4 production and oxidation in one core from each snag was assayed in vitro. A single core produced CH4 under anoxic and oxic conditions, at measured rates of 0.7 and 0.6 ng CH4 g-1 h-1, respectively. Four cores oxidized CH4 under oxic conditions, with an average rate of - 1.13 ± 0.31 ng CH4 g-1 h-1. Illumina sequencing of the V3/V4 region of the 16S rRNA gene sequence revealed diverse microbial communities and indicated oxidative decomposition of deadwood. Methanogens were present in 20% of the snags, with a mean relative abundance of < 0.0001%. Methanotrophs were identified in all snags, with a mean relative abundance of 2% and represented the sole CH4-cycling communities in 80% of the snags. These data indicate potential for microbial attenuation of CH4 emissions across the snag-atmosphere interface in ghost forests. A better understanding of the environmental drivers of snag-associated microbial communities is necessary to forecast the response of CH4 cycling in coastal ghost forest wetlands to a shifting coastal landscape.
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Affiliation(s)
- Mary Jane Carmichael
- Departments of Biology and Environmental Studies, Hollins University, Roanoke, VA, 24020, USA.
| | - Melinda Martinez
- U.S. Geological Survey, Eastern Ecological Science Center, Laurel, MD, 20708, USA
| | - Suzanna L Bräuer
- Department of Biology, Appalachian State University, Boone, NC, 28608, USA
| | - Marcelo Ardón
- Department of Forestry and Environmental Resources, North Carolina State University, Raleigh, NC, 27695, USA
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Campbell BC, Greenfield P, Barnhart EP, Gong S, Midgley DJ, Paulsen IT, George SC. Krumholzibacteriota and Deltaproteobacteria contain rare genetic potential to liberate carbon from monoaromatic compounds in subsurface coal seams. mBio 2024; 15:e0173523. [PMID: 38345372 PMCID: PMC10936416 DOI: 10.1128/mbio.01735-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Accepted: 01/09/2024] [Indexed: 03/14/2024] Open
Abstract
Biogenic methane in subsurface coal seam environments is produced by diverse consortia of microbes. Although this methane is useful for global energy security, it remains unclear which microbes can liberate carbon from the coal. Most of this carbon is relatively resistant to biodegradation, as it is contained within aromatic rings. Thus, to explore for coal-degrading taxa in the subsurface, this study reconstructed relevant metagenome-assembled genomes (MAGs) from coal seams by using a key genomic marker for the anaerobic degradation of monoaromatic compounds as a guide: the benzoyl-CoA reductase gene (bcrABCD). Three MAGs were identified with this genetic potential. The first represented a novel taxon from the Krumholzibacteriota phylum, which this study is the first to describe. This Krumholzibacteriota MAG contained a full set of genes for benzoyl-CoA dearomatization, in addition to other genes for anaerobic catabolism of monoaromatics. Analysis of Krumholzibacteriota MAGs from other environments revealed that this genetic potential may be common, and thus, Krumholzibacteriota may be important organisms for the liberation of recalcitrant carbon in a broad range of environments. Moreover, the assembly and characterization of two Syntrophorhabdus aromaticivorans MAGs from different continents and a Syntrophaceae sp. MAG implicate the Deltaproteobacteria class in coal seam monoaromatic degradation. Each of these taxa are potential rate-limiting organisms for subsurface coal-to-methane biodegradation. Their description here provides some understanding of their function within the coal seam microbiome and will help inform future efforts in coal bed methane stimulation, anoxic bioremediation of organic pollutants, and assessments of anoxic, subsurface carbon cycling and emissions.IMPORTANCESubsurface coal seams are highly anoxic, oligotrophic environments, where the main source of carbon is "locked away" within aromatic rings. Despite these challenges, many coal seams accumulate biogenic methane, implying that the coal seam microbiome is "unlocking" this carbon source in situ. For over two decades, researchers have endeavored to understand which organisms perform these processes. This study provides the first descriptions of organisms with this genetic potential from the coal seam environment. Here, we report metagenomic insights into carbon liberation from aromatic molecules and the degradation pathways involved and describe a Krumholzibacteriota, two Syntrophorhabdus aromaticivorans, and a Syntrophaceae MAG that contain this genetic potential. This is also the first time that the Krumholzibacteriota phylum has been implicated in anaerobic dearomatization of aromatic hydrocarbons. This potential is identified here in numerous MAGs from other terrestrial and marine subsurface habitats, implicating the Krumholzibacteriota in carbon-cycling processes across a broad range of environments.
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Affiliation(s)
- Bronwyn C. Campbell
- Environment Business Unit, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Floreat, Western Australia, Australia
- School of Natural Sciences, Macquarie University, North Ryde, New South Wales, Australia
| | - Paul Greenfield
- School of Natural Sciences, Macquarie University, North Ryde, New South Wales, Australia
- Energy Business Unit, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Lindfield, New South Wales, Australia
| | - Elliott P. Barnhart
- U.S. Geological Survey, Wyoming-Montana Water Science Center, Helena, Montana, USA
| | - Se Gong
- Energy Business Unit, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Lindfield, New South Wales, Australia
| | - David J. Midgley
- Energy Business Unit, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Lindfield, New South Wales, Australia
| | - Ian T. Paulsen
- School of Natural Sciences, Macquarie University, North Ryde, New South Wales, Australia
| | - Simon C. George
- School of Natural Sciences, Macquarie University, North Ryde, New South Wales, Australia
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Hong P, Sun X, Yuan S, Wang Y, Gong S, Zhang Y, Sang P, Xiao B, Shu Y. Nitrogen removal intensification of biofilm through bioaugmentation with Methylobacterium gregans DC-1 during wastewater treatment. CHEMOSPHERE 2024; 352:141467. [PMID: 38387667 DOI: 10.1016/j.chemosphere.2024.141467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 01/24/2024] [Accepted: 02/14/2024] [Indexed: 02/24/2024]
Abstract
The increasing concern for environmental remediation has led to a search for effective methods to remove eutrophic nutrients. In this study, Methylobacterium gregans DC-1 was utilized to improve nitrogen removal in a sequencing batch biofilm reactor (SBBR) via aerobic denitrification. This bacterium has the extraordinary characteristics of strong auto-aggregation and a high ability to remove nitrogen efficiently, making it an ideal candidate for enhanced treatment of nitrogen-rich wastewater. This strain was used for the bioassessment of a test reactor (SBBRbio), which showed a shorter biofilm formation time compared to a control reactor (SBBRcon) without this strain inoculation. Moreover, the enhanced biofilm was enriched in TB-EPS and had a wider variety of protein secondary structures than SBBRcon. During the stabilization phase of SBBRbio, the EPS molecules showed the highest proportion of intermolecular hydrogen bonding. It is possible that bioaugmentation with this strain positively affects the structural stability of biofilm. At influent ammonia loadings of 100 and 150 mg. L-1, the average reduction of ammonia and nitrate-nitrogen was higher in the experimental system compared to the control system. Additionally, nitrite-N accumulation was lower and N2O production decreased compared to the control. Analysis of the microbial community structure demonstrated successful colonization in the bioreactor by a highly nitrogen-tolerant strain that efficiently removed inorganic nitrogen. These results illustrate the great potential of this type of denitrifying bacteria in the application of bioaugmentation systems.
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Affiliation(s)
- Pei Hong
- School of Ecology and Environment, College of Life Sciences, Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang Basin Co-founded by Anhui Province and Ministry of Education, Anhui Normal University, Wuhu 241002, China
| | - Xiaohui Sun
- School of Ecology and Environment, College of Life Sciences, Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang Basin Co-founded by Anhui Province and Ministry of Education, Anhui Normal University, Wuhu 241002, China
| | - Saibo Yuan
- Ecological Environment Monitoring and Scientific Research Center, Ecology and Environment Supervision and Administration Bureau of Yangtze Valley, Ministry of Ecology and Environment of the People's Republic of China, Wuhan 430014, China.
| | - Yu Wang
- School of Ecology and Environment, College of Life Sciences, Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang Basin Co-founded by Anhui Province and Ministry of Education, Anhui Normal University, Wuhu 241002, China
| | - Shihao Gong
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, 100872, Hong Kong
| | - Yancheng Zhang
- School of Ecology and Environment, College of Life Sciences, Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang Basin Co-founded by Anhui Province and Ministry of Education, Anhui Normal University, Wuhu 241002, China
| | - Pengcheng Sang
- School of Ecology and Environment, College of Life Sciences, Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang Basin Co-founded by Anhui Province and Ministry of Education, Anhui Normal University, Wuhu 241002, China
| | - Bangding Xiao
- Key Laboratory of Algal Biology of the Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China
| | - Yilin Shu
- School of Ecology and Environment, College of Life Sciences, Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang Basin Co-founded by Anhui Province and Ministry of Education, Anhui Normal University, Wuhu 241002, China.
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Keithley AE, Gomez-Alvarez V, Williams D, Ryu H, Lytle DA. Depth profiles of biological aerated contactors: Characterizing microbial activity treating reduced contaminants. JOURNAL OF WATER PROCESS ENGINEERING 2023; 56:1-11. [PMID: 38357328 PMCID: PMC10866302 DOI: 10.1016/j.jwpe.2023.104360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/16/2024]
Abstract
The biological treatment process consisting of an aerated contactor and filter is effective for groundwaters containing elevated ammonia and other reduced contaminants, including iron, manganese, arsenic, and methane. Depth profiles characterizing microbial activity across aerated contactors are lacking. A 1-year pilot study comparing gravel- and ceramic-packed contactors was conducted, and media depth profile samples were collected at the conclusion of the study. Media and water samples also were collected from pilot-scale aerated contactors at 4 other water systems. Water quality, media surface metals concentrations, and a suite of biofilm parameters were analyzed. Media surface metals concentrations were greatest at the influent end. ATP concentrations, extracellular polymeric substances, and extracellular enzyme activities tended to be similar across depth. Bacteria and functional genes involved in contaminant oxidation co-occurred and tended to decrease across depth, but were not correlated to the media metals concentration. Microbial community composition changed with depth, and the diversity either decreased or remained similar. The microbial activity profiles through aerated contactors differed from what is typically reported for groundwater biofilters, suggesting that the different reactor flow and dissolved oxygen profiles impacted the microbial community.
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Affiliation(s)
- Asher E. Keithley
- U.S. Environmental Protection Agency, ORD, CESER, WID, Cincinnati, OH 45268, United States
| | - Vicente Gomez-Alvarez
- U.S. Environmental Protection Agency, ORD, CESER, WID, Cincinnati, OH 45268, United States
| | - Daniel Williams
- U.S. Environmental Protection Agency, ORD, CESER, WID, Cincinnati, OH 45268, United States
| | - Hodon Ryu
- U.S. Environmental Protection Agency, ORD, CESER, WID, Cincinnati, OH 45268, United States
| | - Darren A. Lytle
- U.S. Environmental Protection Agency, ORD, CESER, WID, Cincinnati, OH 45268, United States
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6
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Albright S, Louca S. Trait biases in microbial reference genomes. Sci Data 2023; 10:84. [PMID: 36759614 PMCID: PMC9911409 DOI: 10.1038/s41597-023-01994-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 01/31/2023] [Indexed: 02/11/2023] Open
Abstract
Common culturing techniques and priorities bias our discovery towards specific traits that may not be representative of microbial diversity in nature. So far, these biases have not been systematically examined. To address this gap, here we use 116,884 publicly available metagenome-assembled genomes (MAGs, completeness ≥80%) from 203 surveys worldwide as a culture-independent sample of bacterial and archaeal diversity, and compare these MAGs to the popular RefSeq genome database, which heavily relies on cultures. We compare the distribution of 12,454 KEGG gene orthologs (used as trait proxies) in the MAGs and RefSeq genomes, while controlling for environment type (ocean, soil, lake, bioreactor, human, and other animals). Using statistical modeling, we then determine the conditional probabilities that a species is represented in RefSeq depending on its genetic repertoire. We find that the majority of examined genes are significantly biased for or against in RefSeq. Our systematic estimates of gene prevalences across bacteria and archaea in nature and gene-specific biases in reference genomes constitutes a resource for addressing these issues in the future.
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Affiliation(s)
- Sage Albright
- Department of Biology, University of Oregon, Eugene, USA
| | - Stilianos Louca
- Department of Biology, University of Oregon, Eugene, USA. .,Institute of Ecology and Evolution, University of Oregon, Eugene, USA.
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7
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Microbial Activities and Selection from Surface Ocean to Subseafloor on the Namibian Continental Shelf. Appl Environ Microbiol 2022; 88:e0021622. [PMID: 35404072 PMCID: PMC9088280 DOI: 10.1128/aem.00216-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [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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Guo R, Ma X, Zhang J, Liu C, Thu CA, Win TN, Aung NL, Win HS, Naing S, Li H, Zhou F, Wang P. Microbial community structures and important taxa across oxygen gradients in the Andaman Sea and eastern Bay of Bengal epipelagic waters. Front Microbiol 2022; 13:1041521. [PMID: 36406446 PMCID: PMC9667114 DOI: 10.3389/fmicb.2022.1041521] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Accepted: 09/29/2022] [Indexed: 05/01/2023] Open
Abstract
In oceanic oxygen minimum zones (OMZs), the abundances of aerobic organisms significantly decrease and energy shifts from higher trophic levels to microorganisms, while the microbial communities become critical drivers of marine biogeochemical cycling activities. However, little is known of the microbial ecology of the Andaman Sea and eastern Bay of Bengal (BoB) OMZs. In the present study, a total of 131 samples which from the Andaman Sea and eastern BoB epipelagic waters were analyzed. The microbial community distribution patterns across oxygen gradients, including oxygenic zones (OZs, dissolved oxygen [DO] ≥ 2 mg/L), oxygen limited zones (OLZs, 0.7 mg/L < DO < 2 mg/L), and OMZs (DO ≤ 0.7 mg/L), were investigated. Mantel tests and Spearman's correlation analysis revealed that DO was the most important driver of microbial community structures among several environmental factors. Microbial diversity, richness, and evenness were highest in the OLZs and lowest in the OZs. The microbial community compositions of OZ and OMZ waters were significantly different. Random forest analysis revealed 24 bioindicator taxa that differentiated OZ, OLZ, and OMZ water communities. These bioindicator taxa included Burkholderiaceae, HOC36, SAR11 Clade IV, Thioglobaceae, Nitrospinaceae, SAR86, and UBA10353. Further, co-occurrence network analysis revealed that SAR202, AEGEAN-169, UBA10353, SAR406, and Rhodobacteraceae were keystone taxa among the entire interaction network of the microbial communities. Functional prediction further indicated that the relative abundances of microbial populations involved in nitrogen and sulfur cycling were higher in OMZs. Several microbial taxa, including the Thioglobaceae, Nitrospinaceae, SAR202, SAR406, WPS-2, UBA10353, and Woeseiaceae, may be involved in nitrogen and/or sulfur cycling, while also contributing to oxygen consumption in these waters. This study consequently provides new insights into the microbial community structures and potentially important taxa that contribute to oxygen consumption in the Andaman Sea and eastern BoB OMZ.
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Affiliation(s)
- Ruoyu Guo
- Key Laboratory of Marine Ecosystem Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China
- Observation and Research Station of Yangtze River Delta Marine Ecosystems, Ministry of Natural Resources, Zhoushan, China
| | - Xiao Ma
- Observation and Research Station of Yangtze River Delta Marine Ecosystems, Ministry of Natural Resources, Zhoushan, China
- State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China
| | - Jingjing Zhang
- Key Laboratory of Marine Ecosystem Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China
| | - Chenggang Liu
- Key Laboratory of Marine Ecosystem Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China
| | - Chit Aung Thu
- Research and Development Section, Department of Fisheries, Naypyidaw, Myanmar
| | - Tun Naing Win
- Department of Meteorology and Hydrology, Ministry of Transport and Communication, Naypyidaw, Myanmar
| | - Nyan Lin Aung
- Environmental Conservation Department, Ministry of Natural Resources and Environmental Conservation, Naypyidaw, Myanmar
| | - Hlaing Swe Win
- National Analytical Laboratory, Department of Research in Innovation, Ministry of Education, Naypyidaw, Myanmar
| | - Sanda Naing
- Port and Harbour Engineering Department, Myanmar Maritime University, Thanlyin, Myanmar
| | - Hongliang Li
- Key Laboratory of Marine Ecosystem Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China
| | - Feng Zhou
- Observation and Research Station of Yangtze River Delta Marine Ecosystems, Ministry of Natural Resources, Zhoushan, China
- State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China
- *Correspondence: Feng Zhou,
| | - Pengbin Wang
- Key Laboratory of Marine Ecosystem Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China
- Observation and Research Station of Yangtze River Delta Marine Ecosystems, Ministry of Natural Resources, Zhoushan, China
- Pengbin Wang,
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9
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Kuroda K, Narihiro T, Nobu MK, Tobo A, Yamauchi M, Yamada M. Ecogenomics Reveals Microbial Metabolic Networks in a Psychrophilic Methanogenic Bioreactor Treating Soy Sauce Production Wastewater. Microbes Environ 2021; 36. [PMID: 34588388 PMCID: PMC8674449 DOI: 10.1264/jsme2.me21045] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
An ecogenomic analysis of the methanogenic microbial community in a laboratory-scale up-flow anaerobic sludge blanket (UASB) reactor treating soy sauce-processing wastewater revealed a synergistic metabolic network. Granular sludge samples were collected from the UASB reactor operated under psychrophilic (20°C) conditions with a COD removal rate >75%. A 16S rRNA gene amplicon sequencing-based microbial community analysis classified the major microbial taxa as Methanothrix, Methanobacterium, Pelotomaculaceae, Syntrophomonadaceae, Solidesulfovibrio, and members of the phyla Synergistota and Bacteroidota. Draft genomes of dominant microbial populations were recovered by metagenomic shotgun sequencing. Metagenomic- and metatranscriptomic-assisted metabolic reconstructions indicated that Synergistota- and Bacteroidota-related organisms play major roles in the degradation of amino acids. A metagenomic bin of the uncultured Bacteroidales 4484-276 clade encodes genes for proteins that may function in the catabolism of phenylalanine and tyrosine under microaerobic conditions. Syntrophomonadaceae and Pelotomaculaceae oxidize fatty acid byproducts presumably derived from the degradation of amino acids in syntrophic association with aceticlastic and hydrogenotrophic methanogen populations. Solidesulfovibrio organisms are responsible for the reduction of sulfite and may support the activity of hydrogenotrophic methanogens and other microbial populations by providing hydrogen and ammonia using nitrogen fixation-related proteins. Overall, functionally diverse anaerobic organisms unite to form a metabolic network that performs the complete degradation of amino acids in the psychrophilic methanogenic microbiota.
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Affiliation(s)
- Kyohei Kuroda
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST)
| | - Takashi Narihiro
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST)
| | - Masaru K Nobu
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST)
| | - Atsushi Tobo
- Department of Urban Environmental Design and Engineering, National Institute of Technology, Kagoshima College
| | - Masahito Yamauchi
- Department of Urban Environmental Design and Engineering, National Institute of Technology, Kagoshima College
| | - Masayoshi Yamada
- Department of Urban Environmental Design and Engineering, National Institute of Technology, Kagoshima College
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10
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Wallenius AJ, Dalcin Martins P, Slomp CP, Jetten MSM. Anthropogenic and Environmental Constraints on the Microbial Methane Cycle in Coastal Sediments. Front Microbiol 2021; 12:631621. [PMID: 33679659 PMCID: PMC7935538 DOI: 10.3389/fmicb.2021.631621] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Accepted: 01/29/2021] [Indexed: 12/05/2022] Open
Abstract
Large amounts of methane, a potent greenhouse gas, are produced in anoxic sediments by methanogenic archaea. Nonetheless, over 90% of the produced methane is oxidized via sulfate-dependent anaerobic oxidation of methane (S-AOM) in the sulfate-methane transition zone (SMTZ) by consortia of anaerobic methane-oxidizing archaea (ANME) and sulfate-reducing bacteria (SRB). Coastal systems account for the majority of total marine methane emissions and typically have lower sulfate concentrations, hence S-AOM is less significant. However, alternative electron acceptors such as metal oxides or nitrate could be used for AOM instead of sulfate. The availability of electron acceptors is determined by the redox zonation in the sediment, which may vary due to changes in oxygen availability and the type and rate of organic matter inputs. Additionally, eutrophication and climate change can affect the microbiome, biogeochemical zonation, and methane cycling in coastal sediments. This review summarizes the current knowledge on the processes and microorganisms involved in methane cycling in coastal sediments and the factors influencing methane emissions from these systems. In eutrophic coastal areas, organic matter inputs are a key driver of bottom water hypoxia. Global warming can reduce the solubility of oxygen in surface waters, enhancing water column stratification, increasing primary production, and favoring methanogenesis. ANME are notoriously slow growers and may not be able to effectively oxidize methane upon rapid sedimentation and shoaling of the SMTZ. In such settings, ANME-2d (Methanoperedenaceae) and ANME-2a may couple iron- and/or manganese reduction to AOM, while ANME-2d and NC10 bacteria (Methylomirabilota) could couple AOM to nitrate or nitrite reduction. Ultimately, methane may be oxidized by aerobic methanotrophs in the upper millimeters of the sediment or in the water column. The role of these processes in mitigating methane emissions from eutrophic coastal sediments, including the exact pathways and microorganisms involved, are still underexplored, and factors controlling these processes are unclear. Further studies are needed in order to understand the factors driving methane-cycling pathways and to identify the responsible microorganisms. Integration of the knowledge on microbial pathways and geochemical processes is expected to lead to more accurate predictions of methane emissions from coastal zones in the future.
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Affiliation(s)
- Anna J. Wallenius
- Department of Microbiology, Institute for Water and Wetland Research, Radboud University Nijmegen, Nijmegen, Netherlands
| | - Paula Dalcin Martins
- Department of Microbiology, Institute for Water and Wetland Research, Radboud University Nijmegen, Nijmegen, Netherlands
| | - Caroline P. Slomp
- Department of Earth Sciences, Faculty of Geosciences, Utrecht University, Utrecht, Netherlands
| | - Mike S. M. Jetten
- Department of Microbiology, Institute for Water and Wetland Research, Radboud University Nijmegen, Nijmegen, Netherlands
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