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Hackmann TJ. The vast landscape of carbohydrate fermentation in prokaryotes. FEMS Microbiol Rev 2024; 48:fuae016. [PMID: 38821505 PMCID: PMC11187502 DOI: 10.1093/femsre/fuae016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2024] [Revised: 05/23/2024] [Accepted: 05/29/2024] [Indexed: 06/02/2024] Open
Abstract
Fermentation is a type of metabolism carried out by organisms in environments without oxygen. Despite being studied for over 185 years, the diversity and complexity of this metabolism are just now becoming clear. Our review starts with the definition of fermentation, which has evolved over the years and which we help further refine. We then examine the range of organisms that carry out fermentation and their traits. Over one-fourth of all prokaryotes are fermentative, use more than 40 substrates, and release more than 50 metabolic end products. These insights come from studies analyzing records of thousands of organisms. Next, our review examines the complexity of fermentation at the biochemical level. We map out pathways of glucose fermentation in unprecedented detail, covering over 120 biochemical reactions. We also review recent studies coupling genomics and enzymology to reveal new pathways and enzymes. Our review concludes with practical applications for agriculture, human health, and industry. All these areas depend on fermentation and could be improved through manipulating fermentative microbes and enzymes. We discuss potential approaches for manipulation, including genetic engineering, electrofermentation, probiotics, and enzyme inhibitors. We hope our review underscores the importance of fermentation research and stimulates the next 185 years of study.
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Affiliation(s)
- Timothy J Hackmann
- Department of Animal Science, University of California, Davis, CA 95616, United States
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2
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Bouranis JA, Tfaily MM. Inside the microbial black box: a redox-centric framework for deciphering microbial metabolism. Trends Microbiol 2024:S0966-842X(24)00134-3. [PMID: 38825550 DOI: 10.1016/j.tim.2024.05.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Revised: 05/09/2024] [Accepted: 05/10/2024] [Indexed: 06/04/2024]
Abstract
Microbial metabolism influences the global climate and human health and is governed by the balance between NADH and NAD+ through redox reactions. Historically, oxidative (i.e., catabolism) and reductive (i.e., fermentation) pathways have been studied in isolation, obscuring the complete metabolic picture. However, new omics technologies and biotechnological tools now allow an integrated system-level understanding of the drivers of microbial metabolism through observation and manipulation of redox reactions. Here we present perspectives on the importance of viewing microbial metabolism as the dynamic interplay between oxidative and reductive processes and apply this framework to diverse microbial systems. Additionally, we highlight novel biotechnologies to monitor and manipulate microbial redox status to control metabolism in unprecedented ways. This redox-focused systems biology framework enables a more mechanistic understanding of microbial metabolism.
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Affiliation(s)
- John A Bouranis
- Department of Environmental Science, The University of Arizona, Tucson, AZ, 85719, USA
| | - Malak M Tfaily
- Department of Environmental Science, The University of Arizona, Tucson, AZ, 85719, USA.
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3
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Candry P, Flinkstrom Z, Henriikka Winkler MK. Wetlands harbor lactic acid-driven chain elongators. Microbiol Spectr 2024; 12:e0210523. [PMID: 38084977 PMCID: PMC10783096 DOI: 10.1128/spectrum.02105-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Accepted: 11/02/2023] [Indexed: 01/13/2024] Open
Abstract
IMPORTANCE Wetlands are globally significant carbon cycling hotspots that both sequester large amounts of CO2 as soil carbon as well as emit a third of all CH4 globally. Their outsized role in the global carbon cycle makes it critical to understand microbial processes contributing to carbon breakdown and storage in these ecosystems. Here, we confirm the presence of chain-elongating organisms in freshwater wetland soils. These organisms take small carbon compounds formed during the breakdown of biomass and turn them into larger compounds (six to eight carbon organic acids) that may potentially contribute to the formation of soil organic matter and long-term carbon storage. Moreover, we find that these chain-elongating organisms may be widely distributed in wetlands globally. Future work should identify these organisms' contribution to carbon cycling in wetlands and the potential role of the products they form in carbon sequestration in wetlands.
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Affiliation(s)
- Pieter Candry
- Civil and Environmental Engineering, University of Washington, Seattle, Washington, USA
| | - Zachary Flinkstrom
- Civil and Environmental Engineering, University of Washington, Seattle, Washington, USA
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4
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Hutchinson TF, Kessler AJ, Wong WW, Hall P, Leung PM, Jirapanjawat T, Greening C, Glud RN, Cook PLM. Microorganisms oxidize glucose through distinct pathways in permeable and cohesive sediments. THE ISME JOURNAL 2024; 18:wrae001. [PMID: 38365261 PMCID: PMC10939381 DOI: 10.1093/ismejo/wrae001] [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: 12/07/2023] [Revised: 01/01/2024] [Accepted: 01/02/2024] [Indexed: 02/18/2024]
Abstract
In marine sediments, microbial degradation of organic matter under anoxic conditions is generally thought to proceed through fermentation to volatile fatty acids, which are then oxidized to CO2 coupled to the reduction of terminal electron acceptors (e.g. nitrate, iron, manganese, and sulfate). It has been suggested that, in environments with a highly variable oxygen regime, fermentation mediated by facultative anaerobic bacteria (uncoupled to external terminal electron acceptors) becomes the dominant process. Here, we present the first direct evidence for this fermentation using a novel differentially labeled glucose isotopologue assay that distinguishes between CO2 produced from respiration and fermentation. Using this approach, we measured the relative contribution of respiration and fermentation of glucose in a range of permeable (sandy) and cohesive (muddy) sediments, as well as four bacterial isolates. Under anoxia, microbial communities adapted to high-energy sandy or bioturbated sites mediate fermentation via the Embden-Meyerhof-Parnas pathway, in a manner uncoupled from anaerobic respiration. Prolonged anoxic incubation suggests that this uncoupling lasts up to 160 h. In contrast, microbial communities in anoxic muddy sediments (smaller median grain size) generally completely oxidized 13C glucose to 13CO2, consistent with the classical redox cascade model. We also unexpectedly observed that fermentation occurred under oxic conditions in permeable sediments. These observations were further confirmed using pure cultures of four bacteria isolated from permeable sediments. Our results suggest that microbial communities adapted to variable oxygen regimes metabolize glucose (and likely other organic molecules) through fermentation uncoupled to respiration during transient anoxic conditions.
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Affiliation(s)
- Tess F Hutchinson
- Water Studies, School of Chemistry, Monash University, Clayton, VIC 3800, Australia
| | - Adam J Kessler
- School of Earth, Atmosphere & Environment, Monash University, Clayton, VIC 3800, Australia
| | - Wei Wen Wong
- Water Studies, School of Chemistry, Monash University, Clayton, VIC 3800, Australia
| | - Puspitaningsih Hall
- Water Studies, School of Chemistry, Monash University, Clayton, VIC 3800, Australia
| | - Pok Man Leung
- Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia
| | - Thanavit Jirapanjawat
- Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia
| | - Chris Greening
- Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia
| | - Ronnie N Glud
- University of Southern Denmark, HADAL, Nordcee and DIAS, Odense M 5230, Denmark
- Tokyo University of Marine Science and Technology, 4-5-7 Konan, Minato-ku, Tokyo 108-8477, Japan
| | - Perran L M Cook
- Water Studies, School of Chemistry, Monash University, Clayton, VIC 3800, Australia
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Schauberger C, Thamdrup B, Lemonnier C, Trouche B, Poulain J, Wincker P, Arnaud-Haond S, Glud RN, Maignien L. Metagenome-assembled genomes of deep-sea sediments: changes in microbial functional potential lag behind redox transitions. ISME COMMUNICATIONS 2024; 4:ycad005. [PMID: 38282644 PMCID: PMC10809760 DOI: 10.1093/ismeco/ycad005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 11/21/2023] [Accepted: 11/22/2023] [Indexed: 01/30/2024]
Abstract
Hadal sediments are hotspots of microbial activity in the deep sea and exhibit strong biogeochemical gradients. But although these gradients are widely assumed to exert selective forces on hadal microbial communities, the actual relationship between biogeochemistry, functional traits, and microbial community structure remains poorly understood. We tested whether the biogeochemical conditions in hadal sediments select for microbes based on their genomic capacity for respiration and carbohydrate utilization via a metagenomic analysis of over 153 samples from the Atacama Trench region (max. depth = 8085 m). The obtained 1357 non-redundant microbial genomes were affiliated with about one-third of all known microbial phyla, with more than half belonging to unknown genera. This indicated that the capability to withstand extreme hydrostatic pressure is a phylogenetically widespread trait and that hadal sediments are inhabited by diverse microbial lineages. Although community composition changed gradually over sediment depth, these changes were not driven by selection for respiratory or carbohydrate degradation capability in the oxic and nitrogenous zones, except in the case of anammox bacteria and nitrifying archaea. However, selection based on respiration and carbohydrate degradation capacity did structure the communities of the ferruginous zone, where aerobic and nitrogen respiring microbes declined exponentially (half-life = 125-419 years) and were replaced by subsurface communities. These results highlight a delayed response of microbial community composition to selective pressure imposed by redox zonation and indicated that gradual changes in microbial composition are shaped by the high-resilience and slow growth of microbes in the seafloor.
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Affiliation(s)
- Clemens Schauberger
- Hadal & Nordcee, Department of Biology, University of Southern Denmark, Campusvej 55, Odense M 5230, Denmark
| | - Bo Thamdrup
- Hadal & Nordcee, Department of Biology, University of Southern Denmark, Campusvej 55, Odense M 5230, Denmark
| | - Clarisse Lemonnier
- Microbiology of Extreme Environments Laboratory, CNRS, IFREMER, Univ Brest, F-29280 Plouzané, France
| | - Blandine Trouche
- Microbiology of Extreme Environments Laboratory, CNRS, IFREMER, Univ Brest, F-29280 Plouzané, France
| | - Julie Poulain
- Génomique Métabolique, Genoscope, Institut François Jacob, CEA, CNRS,University of Évry, Université Paris-Saclay, 91057 Evry, France
| | - Patrick Wincker
- Génomique Métabolique, Genoscope, Institut François Jacob, CEA, CNRS,University of Évry, Université Paris-Saclay, 91057 Evry, France
| | - Sophie Arnaud-Haond
- MARBEC, CNRS, IRD, Institut Français de Recherche pour L'Exploitation de la Mer, Univ Montpellier, 34200 Sète, France
| | - Ronnie N Glud
- Hadal & Nordcee, Department of Biology, University of Southern Denmark, Campusvej 55, Odense M 5230, Denmark
- Department of Ocean and Environmental Sciences, Tokyo University of Marine Science and Technology, 4-5-7 Konan, Minato-ku, Tokyo 108-8477, Japan
| | - Lois Maignien
- Microbiology of Extreme Environments Laboratory, CNRS, IFREMER, Univ Brest, F-29280 Plouzané, France
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Pan C, Zhao Y, Chen X, Zhang G, Xie L, Wei Z, Song C. Improved carbon sequestration by utilization of ferrous ions during different organic wastes composting. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 347:119188. [PMID: 37801948 DOI: 10.1016/j.jenvman.2023.119188] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 09/21/2023] [Accepted: 09/27/2023] [Indexed: 10/08/2023]
Abstract
The humic acid (HA) possesses a more recalcitrant structure, making it crucial carbon components that improve carbon sequestration. Moreover, ferrous ions could improve microbial activity and enhance compost humification, and their oxidation into iron oxides could adsorb carbon components for sequestration. Based on the advantages of low cost and easy availability of ferrous sulfate (FeSO4), this study investigated the effect of FeSO4 on carbon sequestration during composting. Chicken manure (CM) and food waste (FW) composting were carried out in four treatments, namely control (CM, FW) and 5% (w/w) FeSO4 treated groups (CM+, FW+). Results indicated that FeSO4 increased HA content, improved organic carbon stability. Carbon loss for CM, CM+, FW and FW + treatments were 48.5%, 46.2%, 45.0%, and 40.3%, respectively. Meanwhile, FeSO4 enhanced the function of bacterial taxa involved in HA synthesis in CM + treatment, and improved the number of core bacteria significantly associated with formation of HA and iron oxide. SEM analysis verified that role of FeSO4 was significant in promoting HA synthesis during CM + composting, while it was remarkably in enhancing HA sequestration during FW + composting. This article provided fundamental theoretical backing for enhancing HA production and improving carbon sequestration during different materials composting.
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Affiliation(s)
- Chaonan Pan
- College of Life Science, Northeast Agricultural University, Harbin, 150030, China
| | - Yue Zhao
- College of Life Science, Northeast Agricultural University, Harbin, 150030, China
| | - Xiaomeng Chen
- College of Life Science, Northeast Agricultural University, Harbin, 150030, China
| | - Guogang Zhang
- Tianjin Key Laboratory of Animal and Plant Resistance, College of Life Sciences, Tianjin Normal University, Tianjin, 300387, China
| | - Lina Xie
- Tianjin Key Laboratory of Animal and Plant Resistance, College of Life Sciences, Tianjin Normal University, Tianjin, 300387, China
| | - Zimin Wei
- College of Life Science, Northeast Agricultural University, Harbin, 150030, China; Tianjin Key Laboratory of Animal and Plant Resistance, College of Life Sciences, Tianjin Normal University, Tianjin, 300387, China.
| | - Caihong Song
- College of Life Science, Liaocheng University, Liaocheng, 252000, China
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Chen X, Zhang X, Yu H, Han M, Sun J, Liu G, Ji Y, Zhai C, Zhu L, Shao H, Liang Y, McMinn A, Wang M. Spatio-temporal variation of bacterial community structure in two intertidal sediment types of Jiaozhou Bay. ENVIRONMENTAL RESEARCH 2023; 237:116743. [PMID: 37500038 DOI: 10.1016/j.envres.2023.116743] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 07/11/2023] [Accepted: 07/24/2023] [Indexed: 07/29/2023]
Abstract
The intertidal sediment environment is dynamic and the biofilm bacterial community within it must constantly adapt, but an understanding of the differences in the biofilm bacterial community within sediments of different types is still relatively limited. The semi-enclosed Jiaozhou Bay has a temperate monsoon climate, with strong currents at the mouth of the bay. In this study, the structure of the bacterial community in Jiaozhou Bay sediment biofilms are described using high-throughput 16 S rRNA gene sequencing and the effects of temporal change and different sediment environment types are discussed. Alpha diversity was significantly higher in sandy samples than in muddy samples. Sandy sediments with increased heterogeneity promote bacterial aggregation. Beta diversity analysis showed significant differences between sediment types and between stations. Proteobacteria and Acidobacteria were significantly more abundant at ZQ, while Campilobacterota was significantly more abundant at LC. The relative abundances of Bacteroidetes, Campilobacterota, Firmicutes, and Chloroflexi were significantly higher in the muddy samples, while Actinobacteria and Proteobacteria were higher in the sandy samples. There were different phylum-level biomarkers between sediment types at different stations. There were also different patterns of functional enrichment in biogeochemical cycles between sediment types and stations with the former having more gene families that differed significantly, highlighting their greater role in determining bacterial function. Bacterial amplicon sequence variant variation between months was less than KEGG ortholog variation between months, presumably the temporal change had an impact on shaping the intertidal sediment bacterial community, although this was less clear at the gene family level. Random forest prediction yielded a combination of 43 family-level features that responded well to temporal change, reflecting the influence of temporal change on sediment biofilm bacteria.
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Affiliation(s)
- Xuechao Chen
- College of Marine Life Sciences, Institute of Evolution and Marine Biodiversity, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Center for Ocean Carbon Neutrality, Ocean University of China, Qingdao, 266003, China
| | - Xinran Zhang
- College of Marine Life Sciences, Institute of Evolution and Marine Biodiversity, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Center for Ocean Carbon Neutrality, Ocean University of China, Qingdao, 266003, China
| | - Hao Yu
- College of Marine Life Sciences, Institute of Evolution and Marine Biodiversity, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Center for Ocean Carbon Neutrality, Ocean University of China, Qingdao, 266003, China
| | - Meiaoxue Han
- College of Marine Life Sciences, Institute of Evolution and Marine Biodiversity, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Center for Ocean Carbon Neutrality, Ocean University of China, Qingdao, 266003, China
| | - Jianhua Sun
- College of Marine Life Sciences, Institute of Evolution and Marine Biodiversity, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Center for Ocean Carbon Neutrality, Ocean University of China, Qingdao, 266003, China
| | - Gang Liu
- College of Marine Life Sciences, Institute of Evolution and Marine Biodiversity, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Center for Ocean Carbon Neutrality, Ocean University of China, Qingdao, 266003, China
| | - Yan Ji
- College of Marine Life Sciences, Institute of Evolution and Marine Biodiversity, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Center for Ocean Carbon Neutrality, Ocean University of China, Qingdao, 266003, China
| | - Chuan Zhai
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, TAS, 7001, Australia
| | - Liyan Zhu
- College of Marine Life Sciences, Ocean University of China, Qingdao, 266003, China
| | - Hongbing Shao
- College of Marine Life Sciences, Institute of Evolution and Marine Biodiversity, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Center for Ocean Carbon Neutrality, Ocean University of China, Qingdao, 266003, China; UMT-OUC Joint Centre for Marine Studies, Qingdao, 266003, China
| | - Yantao Liang
- College of Marine Life Sciences, Institute of Evolution and Marine Biodiversity, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Center for Ocean Carbon Neutrality, Ocean University of China, Qingdao, 266003, China; UMT-OUC Joint Centre for Marine Studies, Qingdao, 266003, China.
| | - Andrew McMinn
- College of Marine Life Sciences, Institute of Evolution and Marine Biodiversity, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Center for Ocean Carbon Neutrality, Ocean University of China, Qingdao, 266003, China; Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, TAS, 7001, Australia.
| | - Min Wang
- College of Marine Life Sciences, Institute of Evolution and Marine Biodiversity, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Center for Ocean Carbon Neutrality, Ocean University of China, Qingdao, 266003, China; UMT-OUC Joint Centre for Marine Studies, Qingdao, 266003, China; Haide College, Ocean University of China, Qingdao, 266003, China; The Affiliated Hospital of Qingdao University, Qingdao, 266000, China.
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8
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Hackmann TJ, Zhang B. The phenotype and genotype of fermentative prokaryotes. SCIENCE ADVANCES 2023; 9:eadg8687. [PMID: 37756392 PMCID: PMC10530074 DOI: 10.1126/sciadv.adg8687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Accepted: 08/25/2023] [Indexed: 09/29/2023]
Abstract
Fermentation is a type of metabolism pervasive in oxygen-deprived environments. Despite its importance, we know little about the range and traits of organisms that carry out this metabolism. Our study addresses this gap with a comprehensive analysis of the phenotype and genotype of fermentative prokaryotes. We assembled a dataset with phenotypic records of 8350 organisms plus 4355 genomes and 13.6 million genes. Our analysis reveals fermentation is both widespread (in ~30% of prokaryotes) and complex (forming ~300 combinations of metabolites). Furthermore, it points to previously uncharacterized proteins involved in this metabolism. Previous studies suggest that metabolic pathways for fermentation are well understood, but metabolic models built in our study show gaps in our knowledge. This study demonstrates the complexity of fermentation while showing that there is still much to learn about this metabolism. All resources in our study can be explored by the scientific community with an online, interactive tool.
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Affiliation(s)
| | - Bo Zhang
- Department of Chemical Engineering, University of California, Santa Barbara, CA, USA
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Nauer PA, Kessler AJ, Hall P, Popa ME, ten Hietbrink S, Hutchinson T, Wong WW, Attard K, Glud RN, Greening C, Cook PLM. Pulses of labile carbon cause transient decoupling of fermentation and respiration in permeable sediments. LIMNOLOGY AND OCEANOGRAPHY 2023; 68:2141-2152. [PMID: 38516532 PMCID: PMC10952694 DOI: 10.1002/lno.12411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 12/07/2022] [Accepted: 07/15/2023] [Indexed: 03/23/2024]
Abstract
Dihydrogen (H2) is an important intermediate in anaerobic microbial processes, and concentrations are tightly controlled by thermodynamic limits of consumption and production. However, recent studies reported unusual H2 accumulation in permeable marine sediments under anoxic conditions, suggesting decoupling of fermentation and sulfate reduction, the dominant respiratory process in anoxic permeable marine sediments. Yet, the extent, prevalence and potential triggers for such H2 accumulation and decoupling remain unknown. We surveyed H2 concentrations in situ at different settings of permeable sand and found that H2 accumulation was only observed during a coral spawning event on the Great Barrier Reef. A flume experiment with organic matter addition to the water column showed a rapid accumulation of hydrogen within the sediment. Laboratory experiments were used to explore the effect of oxygen exposure, physical disturbance and organic matter inputs on H2 accumulation. Oxygen exposure had little effect on H2 accumulation in permeable sediments suggesting both fermenters and sulfate reducers survive and rapidly resume activity after exposure to oxygen. Mild physical disturbance mimicking sediment resuspension had little effect on H2 accumulation; however, vigorous shaking led to a transient accumulation of H2 and release of dissolved organic carbon suggesting mechanical disturbance and cell destruction led to organic matter release and transient decoupling of fermenters and sulfate reducers. In summary, the highly dynamic nature of permeable sediments and its microbial community allows for rapid but transient decoupling of fermentation and respiration after a C pulse, leading to high H2 levels in the sediment.
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Affiliation(s)
- Philipp A. Nauer
- Water StudiesSchool of Chemistry, Monash UniversityClaytonVictoriaAustralia
| | - Adam J. Kessler
- School of Earth Atmosphere and Environment, Monash UniversityClaytonVictoriaAustralia
| | | | - Maria Elena Popa
- Institute for Marine and Atmospheric research Utrecht (IMAU), Utrecht UniversityUtrechtNetherlands
| | - Sophie ten Hietbrink
- Institute for Marine and Atmospheric research Utrecht (IMAU), Utrecht UniversityUtrechtNetherlands
| | - Tess Hutchinson
- Water StudiesSchool of Chemistry, Monash UniversityClaytonVictoriaAustralia
| | - Wei Wen Wong
- Water StudiesSchool of Chemistry, Monash UniversityClaytonVictoriaAustralia
| | - Karl Attard
- Nordcee and HADAL, Department of BiologyUniversity of Southern DenmarkOdense MDenmark
- Danish Institute for Advanced Study, University of Southern DenmarkOdense MDenmark
| | - Ronnie N. Glud
- Nordcee and HADAL, Department of BiologyUniversity of Southern DenmarkOdense MDenmark
- Danish Institute for Advanced Study, University of Southern DenmarkOdense MDenmark
- Department of Ocean and Environmental SciencesTokyo University of Marine Science and TechnologyTokyoJapan
| | - Chris Greening
- Department of MicrobiologyBiomedicine Discovery InstituteClaytonVictoriaAustralia
| | - Perran L. M. Cook
- Water StudiesSchool of Chemistry, Monash UniversityClaytonVictoriaAustralia
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10
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Zhang ZF, Liu LR, Pan YP, Pan J, Li M. Long-read assembled metagenomic approaches improve our understanding on metabolic potentials of microbial community in mangrove sediments. MICROBIOME 2023; 11:188. [PMID: 37612768 PMCID: PMC10464287 DOI: 10.1186/s40168-023-01630-x] [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: 04/15/2023] [Accepted: 07/21/2023] [Indexed: 08/25/2023]
Abstract
BACKGROUND Mangrove wetlands are coastal ecosystems with important ecological features and provide habitats for diverse microorganisms with key roles in nutrient and biogeochemical cycling. However, the overall metabolic potentials and ecological roles of microbial community in mangrove sediment are remained unanswered. In current study, the microbial and metabolic profiles of prokaryotic and fungal communities in mangrove sediments were investigated using metagenomic analysis based on PacBio single-molecule real time (SMRT) and Illumina sequencing techniques. RESULTS Comparing to Illumina short reads, the incorporation of PacBio long reads significantly contributed to more contiguous assemblies, yielded more than doubled high-quality metagenome-assembled genomes (MAGs), and improved the novelty of the MAGs. Further metabolic reconstruction for recovered MAGs showed that prokaryotes potentially played an essential role in carbon cycling in mangrove sediment, displaying versatile metabolic potential for degrading organic carbons, fermentation, autotrophy, and carbon fixation. Mangrove fungi also functioned as a player in carbon cycling, potentially involved in the degradation of various carbohydrate and peptide substrates. Notably, a new candidate bacterial phylum named as Candidatus Cosmopoliota with a ubiquitous distribution is proposed. Genomic analysis revealed that this new phylum is capable of utilizing various types of organic substrates, anaerobic fermentation, and carbon fixation with the Wood-Ljungdahl (WL) pathway and the reverse tricarboxylic acid (rTCA) cycle. CONCLUSIONS The study not only highlights the advantages of HiSeq-PacBio Hybrid assembly for a more complete profiling of environmental microbiomes but also expands our understanding of the microbial diversity and potential roles of distinct microbial groups in biogeochemical cycling in mangrove sediment. Video Abstract.
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Affiliation(s)
- Zhi-Feng Zhang
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, Shenzhen, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, China
- Present Address: Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, 511458, China
| | - Li-Rui Liu
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, Shenzhen, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, China
| | - Yue-Ping Pan
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, Shenzhen, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, China
| | - Jie Pan
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, Shenzhen, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, China
| | - Meng Li
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, Shenzhen, China.
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, China.
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11
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Zhao Y, Li J, Liu Q, Qi Z, Li X, Zhang Q, Sui J, Wang C, Peng Y. Fast start-up and stable operation of mainstream anammox without inoculation in an A 2/O process treating low COD/N real municipal wastewater. WATER RESEARCH 2023; 231:119598. [PMID: 36669306 DOI: 10.1016/j.watres.2023.119598] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 12/30/2022] [Accepted: 01/08/2023] [Indexed: 06/17/2023]
Abstract
It is of great significance to start up the anammox process in the most commonly used anaerobic-anoxic-oxic (A2/O) process in treating mainstream municipal wastewater. Recently, partial-denitrification/anammox (PD/A) has attracted increasing interest as a new avenue in mainstream. This study investigated the in situ start-up of PD/A process in a traditional A2/O process. The PD/A system was rapidly started up within 60 days by adding virgin carriers into the anoxic zone and then run stably for the next 90 days. The in situ anammox activity reached 1.0 ± 0.1 mg NH4+-N/L/h contributing 37.9 ± 6.2% of total nitrogen removal. As a result, the nitrogen removal efficiency of the system increased by 16.9%. The anammox bacteria (AnAOB) on the anoxic biofilms were enriched with a doubling time of 14.53d, and the relative abundance reached 2.49% on day 150. Phylogenetic analysis showed the dominant AnAOB was related to Ca. Brocadia sp. 40, which was the only detected anammox genus in the anoxic biofilm from start-up to stable operation. Batch tests and qPCR results revealed that compared with the floc sludge, the anoxic biofilms exhibited NO2- accumulation driven by PD and performed a better coordination between denitrifiers and AnAOB. Overall, this study provides great confidence for the in situ fast start-up of mainstream anammox using conventional activated sludge.
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Affiliation(s)
- Yang Zhao
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, China
| | - Jianwei Li
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, China
| | - Qiyu Liu
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, China
| | - Zhao Qi
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, China
| | - Xiyao Li
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, China
| | - Qiong Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, China
| | - Jun Sui
- Shouhui Lantian Engineering and Technology Co.Ltd, Guangdong 510075, China
| | - Chuanxin Wang
- Shouhui Lantian Engineering and Technology Co.Ltd, Guangdong 510075, China
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, China.
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12
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van Erk MR, Bourceau OM, Moncada C, Basu S, Hansel CM, de Beer D. Reactive oxygen species affect the potential for mineralization processes in permeable intertidal flats. Nat Commun 2023; 14:938. [PMID: 36804536 PMCID: PMC9941506 DOI: 10.1038/s41467-023-35818-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Accepted: 01/03/2023] [Indexed: 02/22/2023] Open
Abstract
Intertidal permeable sediments are crucial sites of organic matter remineralization. These sediments likely have a large capacity to produce reactive oxygen species (ROS) because of shifting oxic-anoxic interfaces and intense iron-sulfur cycling. Here, we show that high concentrations of the ROS hydrogen peroxide are present in intertidal sediments using microsensors, and chemiluminescent analysis on extracted porewater. We furthermore investigate the effect of ROS on potential rates of microbial degradation processes in intertidal surface sediments after transient oxygenation, using slurries that transitioned from oxic to anoxic conditions. Enzymatic removal of ROS strongly increases rates of aerobic respiration, sulfate reduction and hydrogen accumulation. We conclude that ROS are formed in sediments, and subsequently moderate microbial mineralization process rates. Although sulfate reduction is completely inhibited in the oxic period, it resumes immediately upon anoxia. This study demonstrates the strong effects of ROS and transient oxygenation on the biogeochemistry of intertidal sediments.
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Affiliation(s)
- Marit R van Erk
- Max Planck Institute for Marine Microbiology, Bremen, Germany. .,Department of Earth Sciences, Utrecht University, Utrecht, The Netherlands.
| | | | - Chyrene Moncada
- Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Subhajit Basu
- Max Planck Institute for Marine Microbiology, Bremen, Germany.,School of Health Sciences and Technology (SoHST), University of Petroleum and Energy Studies (UPES), Dehradun, Uttarakhand, 248007, India
| | - Colleen M Hansel
- Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
| | - Dirk de Beer
- Max Planck Institute for Marine Microbiology, Bremen, Germany
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13
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Molecular hydrogen in seawater supports growth of diverse marine bacteria. Nat Microbiol 2023; 8:581-595. [PMID: 36747116 DOI: 10.1038/s41564-023-01322-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 01/05/2023] [Indexed: 02/08/2023]
Abstract
Molecular hydrogen (H2) is an abundant and readily accessible energy source in marine systems, but it remains unknown whether marine microbial communities consume this gas. Here we use a suite of approaches to show that marine bacteria consume H2 to support growth. Genes for H2-uptake hydrogenases are prevalent in global ocean metagenomes, highly expressed in metatranscriptomes and found across eight bacterial phyla. Capacity for H2 oxidation increases with depth and decreases with oxygen concentration, suggesting that H2 is important in environments with low primary production. Biogeochemical measurements of tropical, temperate and subantarctic waters, and axenic cultures show that marine microbes consume H2 supplied at environmentally relevant concentrations, yielding enough cell-specific power to support growth in bacteria with low energy requirements. Conversely, our results indicate that oxidation of carbon monoxide (CO) primarily supports survival. Altogether, H2 is a notable energy source for marine bacteria and may influence oceanic ecology and biogeochemistry.
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14
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Dong X, Lan H, Huang L, Zhang H, Lin X, Weng S, Peng Y, Lin J, Wang JH, Peng J, Yang Y. Metagenomic Views of Microbial Communities in Sand Sediments Associated with Coral Reefs. MICROBIAL ECOLOGY 2023; 85:465-477. [PMID: 35113183 DOI: 10.1007/s00248-021-01957-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 12/29/2021] [Indexed: 06/14/2023]
Abstract
Reef sediments, the home for microbes with high abundances, provide an important source of carbonates and nutrients for the growth and maintenance of coral reefs. However, there is a lack of systematic research on the composition of microbial community in sediments of different geographic sites and their potential effect on nutrient recycling and health of the coral reef ecosystem. In combination of biogeochemical measurements with gene- and genome-centric metagenomics, we assessed microbial community compositions and functional diversity, as well as profiles of antibiotic resistance genes in surface sediments of 16 coral reef sites at different depths from the Xisha islands in the South China Sea. Reef sediment microbiomes are diverse and novel at lower taxonomic ranks, dominated by Proteobacteria and Planctomycetota. Most reef sediment bacteria potentially participate in biogeochemical cycling via oxidizing various organic and inorganic compounds as energy sources. High abundances of Proteobacteria (mostly Rhizobiales and Woeseiales) are metabolically flexible and contain rhodopsin genes. Various classes of antibiotic resistance genes, hosted by diverse bacterial lineages, were identified to confer resistance to multidrug, aminoglycoside, and other antibiotics. Overall, our findings expanded the understanding of reef sediment microbial ecology and provided insights for their link to the coral reef ecosystem health.
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Affiliation(s)
- Xiyang Dong
- School of Marine Sciences, Sun Yat-Sen University, Zhuhai, 519082, China.
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, 519000, China.
| | - Haoyu Lan
- School of Marine Sciences, Sun Yat-Sen University, Zhuhai, 519082, China
| | - Liangtian Huang
- School of Marine Sciences, Sun Yat-Sen University, Zhuhai, 519082, China
| | - Haikun Zhang
- Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, 264003, China
| | - Xianbiao Lin
- School of Marine Sciences, Sun Yat-Sen University, Zhuhai, 519082, China
| | - Shengze Weng
- School of Marine Sciences, Sun Yat-Sen University, Zhuhai, 519082, China
| | - Yongyi Peng
- School of Marine Sciences, Sun Yat-Sen University, Zhuhai, 519082, China
| | - Jia Lin
- School of Marine Sciences, Sun Yat-Sen University, Zhuhai, 519082, China
| | - Jiang-Hai Wang
- School of Marine Sciences, Sun Yat-Sen University, Zhuhai, 519082, China
| | - Juan Peng
- School of Marine Sciences, Sun Yat-Sen University, Zhuhai, 519082, China
| | - Ying Yang
- School of Marine Sciences, Sun Yat-Sen University, Zhuhai, 519082, China.
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, 519000, China.
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15
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Herndl GJ, Bayer B, Baltar F, Reinthaler T. Prokaryotic Life in the Deep Ocean's Water Column. ANNUAL REVIEW OF MARINE SCIENCE 2023; 15:461-483. [PMID: 35834811 DOI: 10.1146/annurev-marine-032122-115655] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The oceanic waters below a depth of 200 m represent, in terms of volume, the largest habitat of the biosphere, harboring approximately 70% of the prokaryotic biomass in the oceanic water column. These waters are characterized by low temperature, increasing hydrostatic pressure, and decreasing organic matter supply with depth. Recent methodological advances in microbial oceanography have refined our view of the ecology of prokaryotes in the dark ocean. Here, we review the ecology of prokaryotes of the dark ocean, present data on the biomass distribution and heterotrophic and chemolithoautotrophic prokaryotic production in the major oceanic basins, and highlight the phylogenetic and functional diversity of this part of the ocean. We describe the connectivity of surface and deep-water prokaryotes and the molecular adaptations of piezophilic prokaryotes to high hydrostatic pressure. We also highlight knowledge gaps in the ecology of the dark ocean's prokaryotes and their role in the biogeochemical cycles in the largest habitat of the biosphere.
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Affiliation(s)
- Gerhard J Herndl
- Department of Functional and Evolutionary Ecology, University of Vienna, Vienna, Austria;
- Department of Marine Microbiology and Biogeochemistry, Royal Netherlands Institute for Sea Research (NIOZ), Utrecht University, Den Burg, The Netherlands
| | - Barbara Bayer
- Department of Microbiology and Ecosystem Science, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
| | - Federico Baltar
- Department of Functional and Evolutionary Ecology, University of Vienna, Vienna, Austria;
| | - Thomas Reinthaler
- Department of Functional and Evolutionary Ecology, University of Vienna, Vienna, Austria;
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16
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Römling U. Is biofilm formation intrinsic to the origin of life? Environ Microbiol 2023; 25:26-39. [PMID: 36655713 PMCID: PMC10086821 DOI: 10.1111/1462-2920.16179] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Accepted: 08/19/2022] [Indexed: 01/21/2023]
Abstract
Biofilms are multicellular, often surface-associated, communities of autonomous cells. Their formation is the natural mode of growth of up to 80% of microorganisms living on this planet. Biofilms refractory towards antimicrobial agents and the actions of the immune system due to their tolerance against multiple environmental stresses. But how did biofilm formation arise? Here, I argue that the biofilm lifestyle has its foundation already in the fundamental, surface-triggered chemical reactions and energy preserving mechanisms that enabled the development of life on earth. Subsequently, prototypical biofilm formation has evolved and diversified concomitantly in composition, cell morphology and regulation with the expansion of prokaryotic organisms and their radiation by occupation of diverse ecological niches. This ancient origin of biofilm formation thus mirrors the harnessing environmental conditions that have been the rule rather than the exception in microbial life. The subsequent emergence of the association of microbes, including recent human pathogens, with higher organisms can be considered as the entry into a nutritional and largely stress-protecting heaven. Nevertheless, basic mechanisms of biofilm formation have surprisingly been conserved and refunctionalized to promote sustained survival in new environments.
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Affiliation(s)
- Ute Römling
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
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17
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Kalathil S, Miller M, Reisner E. Microbial Fermentation of Polyethylene Terephthalate (PET) Plastic Waste for the Production of Chemicals or Electricity. Angew Chem Int Ed Engl 2022; 61:e202211057. [PMID: 36103351 PMCID: PMC9828132 DOI: 10.1002/anie.202211057] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Indexed: 01/12/2023]
Abstract
Ideonella sakaiensis (I. sakaiensis) can grow on polyethylene terephthalate (PET) as the major carbon and energy source. Previous work has shown that PET conversion in the presence of oxygen released carbon dioxide and water while yielding adenosine triphosphate (ATP) through oxidative phosphorylation. This study demonstrates that I. sakaiensis is a facultative anaerobe that ferments PET to the feedstock chemicals acetate and ethanol in the absence of oxygen. In addition to PET, the pure monomer ethylene glycol (EG), the intermediate product ethanol, and the carbohydrate fermentation test substance maltose can also serve as fermenting substrates. Co-culturing of I. sakaiensis with the electrogenic and acetate-consuming Geobacter sulfurreducens produced electricity from PET or EG. This newly identified plastic fermentation process by I. sakaiensis provides thus a novel biosynthetic route to produce high-value chemicals or electricity from plastic waste streams.
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Affiliation(s)
- Shafeer Kalathil
- Yusuf Hamied Department of ChemistryUniversity of CambridgeCambridgeCB2 1EWUK
| | - Melanie Miller
- Yusuf Hamied Department of ChemistryUniversity of CambridgeCambridgeCB2 1EWUK
| | - Erwin Reisner
- Yusuf Hamied Department of ChemistryUniversity of CambridgeCambridgeCB2 1EWUK
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18
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Wu Q, Zou D, Zheng X, Liu F, Li L, Xiao Z. Effects of antibiotics on anaerobic digestion of sewage sludge: Performance of anaerobic digestion and structure of the microbial community. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 845:157384. [PMID: 35843318 DOI: 10.1016/j.scitotenv.2022.157384] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2022] [Revised: 07/09/2022] [Accepted: 07/11/2022] [Indexed: 05/16/2023]
Abstract
As a common biological engineering technology, anaerobic digestion can stabilize sewage sludge and convert the carbon compounds into renewable energy (i.e., methane). However, anaerobic digestion of sewage sludge is severely affected by antibiotics. This review summarizes the effects of different antibiotics on anaerobic digestion of sewage sludge, including production of methane and volatile fatty acids (VFAs), and discusses the impact of antibiotics on biotransformation processes (solubilization, hydrolysis, acidification, acetogenesis and methanogenesis). Moreover, the effects of different antibiotics on microbial community structure (bacteria and archaea) were determined. Most of the research results showed that antibiotics at environmentally relevant concentrations can reduce biogas production mainly by inhibiting methanogenic processes, that is, methanogenic archaea activity, while a few antibiotics can improve biogas production. Moreover, the combination of multiple environmental concentrations of antibiotics inhibited the efficiency of methane production from sludge anaerobic digestion. In addition, some lab-scale pretreatment methods (e.g., ozone, ultrasonic combined ozone, zero-valent iron, Fe3+ and magnetite) can promote the performance of anaerobic digestion of sewage sludge inhibited by antibiotics.
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Affiliation(s)
- Qingdan Wu
- College of Resources and Environment, Hunan Agricultural University, Changsha, Hunan 410128, China; Key Laboratory for Rural Ecosystem Health in Dongting Lake Area of Hunan Province, Changsha, Hunan 410128, China
| | - Dongsheng Zou
- College of Resources and Environment, Hunan Agricultural University, Changsha, Hunan 410128, China; Key Laboratory for Rural Ecosystem Health in Dongting Lake Area of Hunan Province, Changsha, Hunan 410128, China
| | - Xiaochen Zheng
- College of Resources and Environment, Hunan Agricultural University, Changsha, Hunan 410128, China; Key Laboratory for Rural Ecosystem Health in Dongting Lake Area of Hunan Province, Changsha, Hunan 410128, China
| | - Fen Liu
- College of Resources and Environment, Hunan Agricultural University, Changsha, Hunan 410128, China; Key Laboratory for Rural Ecosystem Health in Dongting Lake Area of Hunan Province, Changsha, Hunan 410128, China; College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha, Hunan 410128, China
| | - Longcheng Li
- Beijing Key Laboratory of Biodiversity and Organic Farming, College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China
| | - Zhihua Xiao
- College of Resources and Environment, Hunan Agricultural University, Changsha, Hunan 410128, China; Key Laboratory for Rural Ecosystem Health in Dongting Lake Area of Hunan Province, Changsha, Hunan 410128, China.
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19
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Deng L, Meile C, Fiskal A, Bölsterli D, Han X, Gajendra N, Dubois N, Bernasconi SM, Lever MA. Deposit-feeding worms control subsurface ecosystem functioning in intertidal sediment with strong physical forcing. PNAS NEXUS 2022; 1:pgac146. [PMID: 36714871 PMCID: PMC9802194 DOI: 10.1093/pnasnexus/pgac146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Accepted: 07/25/2022] [Indexed: 06/18/2023]
Abstract
Intertidal sands are global hotspots of terrestrial and marine carbon cycling with strong hydrodynamic forcing by waves and tides and high macrofaunal activity. Yet, the relative importance of hydrodynamics and macrofauna in controlling these ecosystems remains unclear. Here, we compare geochemical gradients and bacterial, archaeal, and eukaryotic gene sequences in intertidal sands dominated by subsurface deposit-feeding worms (Abarenicola pacifica) to adjacent worm-free areas. We show that hydrodynamic forcing controls organismal assemblages in surface sediments, while in deeper layers selective feeding by worms on fine, algae-rich particles strongly decreases the abundance and richness of all three domains. In these deeper layers, bacterial and eukaryotic network connectivity decreases, while percentages of clades involved in degradation of refractory organic matter, oxidative nitrogen, and sulfur cycling increase. Our findings reveal macrofaunal activity as the key driver of biological community structure and functioning, that in turn influence carbon cycling in intertidal sands below the mainly physically controlled surface layer.
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Affiliation(s)
| | - Christof Meile
- Department of Marine Sciences, University of Georgia, 325 Sanford Drive, Athens, GA 30602, USA
| | | | - Damian Bölsterli
- Institute of Biogeochemistry and Pollutant Dynamics, Swiss Federal Institute of Technology, Zurich (ETH Zurich), Universitätstrasse 16, 8092 Zurich, Switzerland
| | | | - Niroshan Gajendra
- Institute of Biogeochemistry and Pollutant Dynamics, Swiss Federal Institute of Technology, Zurich (ETH Zurich), Universitätstrasse 16, 8092 Zurich, Switzerland
| | - Nathalie Dubois
- Department of Surface Waters - Research and Management, Swiss Federal Institute of Aquatic Science and Technology (EAWAG), Überlandstrasse 133, 8600 Dübendorf, Switzerland
- Department of Earth Sciences, Swiss Federal Institute of Technology, Zurich (ETH Zurich), Sonneggstrasse 5, 8092 Zürich, Switzerland
| | - Stefano M Bernasconi
- Department of Earth Sciences, Swiss Federal Institute of Technology, Zurich (ETH Zurich), Sonneggstrasse 5, 8092 Zürich, Switzerland
| | - Mark A Lever
- Institute of Biogeochemistry and Pollutant Dynamics, Swiss Federal Institute of Technology, Zurich (ETH Zurich), Universitätstrasse 16, 8092 Zurich, Switzerland
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20
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Zhao G, Wu B, Zheng X, Chen B, Kappler A, Chu C. Tide-Triggered Production of Reactive Oxygen Species in Coastal Soils. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:11888-11896. [PMID: 35816724 DOI: 10.1021/acs.est.2c03142] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
We report an unrecognized, tidal source of reactive oxygen species (ROS). Using a newly developed ROS-trapping gel film, we observed hot spots for ROS generation within ∼2.5 mm of coastal surface soil. Kinetic analyses showed rapid production of hydroxyl radicals (•OH), superoxide (O2•-), and hydrogen peroxide (H2O2) upon a shift from high tide to low tide. The ROS production exhibited a distinct rhythmic fluctuation. The oscillations of the redox potential and dissolved oxygen concentration followed the same pattern as the •OH production, suggesting the alternating oxic-anoxic conditions as the main geochemical drive for ROS production. Nationwide coastal field investigations confirmed the widespread and sustainable production of ROS via tidal processes (22.1-117.4 μmol/m2/day), which was 5- to 36-fold more efficient than those via classical photochemical routes (1.5-7.6 μmol/m2/day). Analyses of soil physicochemical properties demonstrated that soil redox-metastable components such as redox-active iron minerals and organic matter played a key role in storing electrons at high tide and shuttling electrons to infiltrated oxygen at low tide for ROS production. Our work sheds light on a ubiquitous but previously overlooked tidal source of ROS, which may accelerate carbon and metal cycles as well as pollutant degradation in coastal soils.
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Affiliation(s)
- Guoqiang Zhao
- Faculty of Agriculture, Life, and Environmental Sciences, Zhejiang University, Hangzhou 310058, China
| | - Binbin Wu
- Faculty of Agriculture, Life, and Environmental Sciences, Zhejiang University, Hangzhou 310058, China
| | - Xiaoshan Zheng
- Faculty of Agriculture, Life, and Environmental Sciences, Zhejiang University, Hangzhou 310058, China
| | - Baoliang Chen
- Faculty of Agriculture, Life, and Environmental Sciences, Zhejiang University, Hangzhou 310058, China
| | - Andreas Kappler
- Geomicrobiology, Center for Applied Geosciences, University of Tübingen, 72074 Tübingen, Germany
- Cluster of Excellence: EXC 2124: Controlling Microbes to Fight Infection, 72074 Tübingen, Germany
| | - Chiheng Chu
- Faculty of Agriculture, Life, and Environmental Sciences, Zhejiang University, Hangzhou 310058, China
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21
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Wang L, Qu F, Zhu Z, Zhao Y, Chen X, Shi M, Wei Z. The important role of tricarboxylic acid cycle metabolism pathways and core bacterial communities in carbon sequestration during chicken manure composting. WASTE MANAGEMENT (NEW YORK, N.Y.) 2022; 150:20-29. [PMID: 35785624 DOI: 10.1016/j.wasman.2022.06.034] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Revised: 06/11/2022] [Accepted: 06/26/2022] [Indexed: 06/15/2023]
Abstract
As a kind of livestock manure, chicken manure (CM) was rich in organic matter and microorganisms. However, a large amount of foul gas discharged by its random stacking not only threatened the environment, but also caused harm to human health. In view of the serious carbon loss and the unclear action mechanism of microbial community on carbon metabolism during CM composting, the effect of adding regulators on the sequestration of organic carbon was explored. Therefore, the purpose of this study was to explore the regulation mechanism of adding tricarboxylic acid cycle (TCA cycle) regulators on the core carbon metabolism pathway during CM composting. The results showed that the adenosine triphosphate (ATP) and malonic acid (MA) slowed down organic carbon degradation, resulting in lower carbon loss rate, which were 64.99% (CK), 62.35% (MA), and 61.26% (ATP) in each treatment. By comparing the abundance and structure of the carbon-related bacterial communities in different treatments, it was found that adding ATP and MA not only reduced the bacterial community abundance, but also tended to be similar in bacterial community composition. Moreover, the microbial specificity related to carbon metabolism pathway was enhanced, while the related gene expression and gene abundance were weakened. The regulation of TCA cycle metabolism pathway was confirmed to be the main way to improve organic carbon content. These findings revealed the positive effects of ATP and MA on carbon fixation from the perspective of gene metabolism.
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Affiliation(s)
- Liqin Wang
- College of Life Science, Northeast Agricultural University, Harbin 150030, China
| | - Fengting Qu
- College of Life Science, Northeast Agricultural University, Harbin 150030, China
| | - Zechen Zhu
- College of Life Science, Northeast Agricultural University, Harbin 150030, China
| | - Yue Zhao
- College of Life Science, Northeast Agricultural University, Harbin 150030, China
| | - Xiaomeng Chen
- College of Life Science, Northeast Agricultural University, Harbin 150030, China
| | - Mingzi Shi
- College of Life Science, Northeast Agricultural University, Harbin 150030, China
| | - Zimin Wei
- College of Life Science, Northeast Agricultural University, Harbin 150030, China.
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22
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Greening C, Grinter R. Microbial oxidation of atmospheric trace gases. Nat Rev Microbiol 2022; 20:513-528. [PMID: 35414013 DOI: 10.1038/s41579-022-00724-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/11/2022] [Indexed: 02/06/2023]
Abstract
The atmosphere has recently been recognized as a major source of energy sustaining life. Diverse aerobic bacteria oxidize the three most abundant reduced trace gases in the atmosphere, namely hydrogen (H2), carbon monoxide (CO) and methane (CH4). This Review describes the taxonomic distribution, physiological role and biochemical basis of microbial oxidation of these atmospheric trace gases, as well as the ecological, environmental, medical and astrobiological importance of this process. Most soil bacteria and some archaea can survive by using atmospheric H2 and CO as alternative energy sources, as illustrated through genetic studies on Mycobacterium cells and Streptomyces spores. Certain specialist bacteria can also grow on air alone, as confirmed by the landmark characterization of Methylocapsa gorgona, which grows by simultaneously consuming atmospheric CH4, H2 and CO. Bacteria use high-affinity lineages of metalloenzymes, namely hydrogenases, CO dehydrogenases and methane monooxygenases, to utilize atmospheric trace gases for aerobic respiration and carbon fixation. More broadly, trace gas oxidizers enhance the biodiversity and resilience of soil and marine ecosystems, drive primary productivity in extreme environments such as Antarctic desert soils and perform critical regulatory services by mitigating anthropogenic emissions of greenhouse gases and toxic pollutants.
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Affiliation(s)
- Chris Greening
- Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia. .,Securing Antarctica's Environmental Future, Monash University, Clayton, Victoria, Australia. .,Centre to Impact AMR, Monash University, Clayton, Victoria, Australia.
| | - Rhys Grinter
- Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia.
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23
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Bay SK, Waite DW, Dong X, Gillor O, Chown SL, Hugenholtz P, Greening C. Chemosynthetic and photosynthetic bacteria contribute differentially to primary production across a steep desert aridity gradient. THE ISME JOURNAL 2021; 15:3339-3356. [PMID: 34035443 PMCID: PMC8528921 DOI: 10.1038/s41396-021-01001-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 04/16/2021] [Accepted: 04/28/2021] [Indexed: 02/04/2023]
Abstract
Desert soils harbour diverse communities of aerobic bacteria despite lacking substantial organic carbon inputs from vegetation. A major question is therefore how these communities maintain their biodiversity and biomass in these resource-limiting ecosystems. Here, we investigated desert topsoils and biological soil crusts collected along an aridity gradient traversing four climatic regions (sub-humid, semi-arid, arid, and hyper-arid). Metagenomic analysis indicated these communities vary in their capacity to use sunlight, organic compounds, and inorganic compounds as energy sources. Thermoleophilia, Actinobacteria, and Acidimicrobiia were the most abundant and prevalent bacterial classes across the aridity gradient in both topsoils and biocrusts. Contrary to the classical view that these taxa are obligate organoheterotrophs, genome-resolved analysis suggested they are metabolically flexible, with the capacity to also use atmospheric H2 to support aerobic respiration and often carbon fixation. In contrast, Cyanobacteria were patchily distributed and only abundant in certain biocrusts. Activity measurements profiled how aerobic H2 oxidation, chemosynthetic CO2 fixation, and photosynthesis varied with aridity. Cell-specific rates of atmospheric H2 consumption increased 143-fold along the aridity gradient, correlating with increased abundance of high-affinity hydrogenases. Photosynthetic and chemosynthetic primary production co-occurred throughout the gradient, with photosynthesis dominant in biocrusts and chemosynthesis dominant in arid and hyper-arid soils. Altogether, these findings suggest that the major bacterial lineages inhabiting hot deserts use different strategies for energy and carbon acquisition depending on resource availability. Moreover, they highlight the previously overlooked roles of Actinobacteriota as abundant primary producers and trace gases as critical energy sources supporting productivity and resilience of desert ecosystems.
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Affiliation(s)
- Sean K Bay
- Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia.
- School of Biological Sciences, Monash University, Clayton, VIC, Australia.
| | - David W Waite
- Australian Centre for Ecogenomics, School of Chemistry and Molecular Biosciences, University of Queensland, St Lucia, QLD, Australia
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Xiyang Dong
- School of Marine Sciences, Sun Yat-Sen University, Zhuhai, China
| | - Osnat Gillor
- Zuckerberg Institute for Water Research, Blaustein Institutes for Desert Research, Ben Gurion University of the Negev, Sde Boker, Israel
| | - Steven L Chown
- School of Biological Sciences, Monash University, Clayton, VIC, Australia
| | - Philip Hugenholtz
- Australian Centre for Ecogenomics, School of Chemistry and Molecular Biosciences, University of Queensland, St Lucia, QLD, Australia
| | - Chris Greening
- Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia.
- School of Biological Sciences, Monash University, Clayton, VIC, Australia.
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Chen YJ, Leung PM, Wood JL, Bay SK, Hugenholtz P, Kessler AJ, Shelley G, Waite DW, Franks AE, Cook PLM, Greening C. Metabolic flexibility allows bacterial habitat generalists to become dominant in a frequently disturbed ecosystem. THE ISME JOURNAL 2021; 15:2986-3004. [PMID: 33941890 PMCID: PMC8443593 DOI: 10.1038/s41396-021-00988-w] [Citation(s) in RCA: 61] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 03/25/2021] [Accepted: 04/09/2021] [Indexed: 02/03/2023]
Abstract
Ecological theory suggests that habitat disturbance differentially influences distributions of habitat generalist and specialist species. While well-established for macroorganisms, this theory has rarely been explored for microorganisms. Here we tested these principles in permeable (sandy) sediments, ecosystems with much spatiotemporal variation in resource availability and physicochemical conditions. Microbial community composition and function were profiled in intertidal and subtidal sediments using 16S rRNA gene amplicon sequencing and metagenomics, yielding 135 metagenome-assembled genomes. Community composition and metabolic traits modestly varied with sediment depth and sampling date. Several taxa were highly abundant and prevalent in all samples, including within the orders Woeseiales and Flavobacteriales, and classified as habitat generalists; genome reconstructions indicate these taxa are highly metabolically flexible facultative anaerobes and adapt to resource variability by using different electron donors and acceptors. In contrast, obligately anaerobic taxa such as sulfate reducers and candidate lineage MBNT15 were less abundant overall and only thrived in more stable deeper sediments. We substantiated these findings by measuring three metabolic processes in these sediments; whereas the habitat generalist-associated processes of sulfide oxidation and fermentation occurred rapidly at all depths, the specialist-associated process of sulfate reduction was restricted to deeper sediments. A manipulative experiment also confirmed habitat generalists outcompete specialist taxa during simulated habitat disturbance. Together, these findings show metabolically flexible habitat generalists become dominant in highly dynamic environments, whereas metabolically constrained specialists are restricted to narrower niches. Thus, an ecological theory describing distribution patterns for macroorganisms likely extends to microorganisms. Such findings have broad ecological and biogeochemical ramifications.
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Affiliation(s)
- Ya-Jou Chen
- Department of Microbiology, Biomedicine Discovery Institute, Clayton, VIC, Australia
- School of Biological Sciences, Monash University, Clayton, VIC, Australia
- Department of Natural Resources Sciences, McGill University, Sainte-Anne-de-Bellevue, QC, Canada
| | - Pok Man Leung
- Department of Microbiology, Biomedicine Discovery Institute, Clayton, VIC, Australia
- School of Biological Sciences, Monash University, Clayton, VIC, Australia
| | - Jennifer L Wood
- Department of Physiology, Anatomy and Microbiology, La Trobe University, Bundoora, VIC, Australia
| | - Sean K Bay
- Department of Microbiology, Biomedicine Discovery Institute, Clayton, VIC, Australia
- School of Biological Sciences, Monash University, Clayton, VIC, Australia
| | - Philip Hugenholtz
- Australian Centre for Ecogenomics, School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD, Australia
| | - Adam J Kessler
- Water Studies Centre, School of Chemistry, Monash University, Clayton, VIC, Australia
- School of Earth, Atmosphere and Environment, Monash University, Clayton, VIC, Australia
| | - Guy Shelley
- School of Biological Sciences, Monash University, Clayton, VIC, Australia
| | - David W Waite
- Australian Centre for Ecogenomics, School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD, Australia
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Ashley E Franks
- Department of Physiology, Anatomy and Microbiology, La Trobe University, Bundoora, VIC, Australia
| | - Perran L M Cook
- Water Studies Centre, School of Chemistry, Monash University, Clayton, VIC, Australia.
| | - Chris Greening
- Department of Microbiology, Biomedicine Discovery Institute, Clayton, VIC, Australia.
- School of Biological Sciences, Monash University, Clayton, VIC, Australia.
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25
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Hydrodynamic disturbance controls microbial community assembly and biogeochemical processes in coastal sediments. ISME JOURNAL 2021; 16:750-763. [PMID: 34584214 PMCID: PMC8857189 DOI: 10.1038/s41396-021-01111-9] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 09/06/2021] [Accepted: 09/08/2021] [Indexed: 01/04/2023]
Abstract
The microbial community composition and biogeochemical dynamics of coastal permeable (sand) sediments differs from cohesive (mud) sediments. Tide- and wave-driven hydrodynamic disturbance causes spatiotemporal variations in oxygen levels, which select for microbial generalists and disrupt redox cascades. In this work, we profiled microbial communities and biogeochemical dynamics in sediment profiles from three sites varying in their exposure to hydrodynamic disturbance. Strong variations in sediment geochemistry, biogeochemical activities, and microbial abundance, composition, and capabilities were observed between the sites. Most of these variations, except for microbial abundance and diversity, significantly correlated with the relative disturbance level of each sample. In line with previous findings, metabolically flexible habitat generalists (e.g., Flavobacteriaceae, Woeseaiceae, Rhodobacteraceae) dominated in all samples. However, we present evidence that aerobic specialists such as ammonia-oxidizing archaea (Nitrosopumilaceae) were more abundant and active in more disturbed samples, whereas bacteria capable of sulfate reduction (e.g., uncultured Desulfobacterales), dissimilatory nitrate reduction to ammonium (DNRA; e.g., Ignavibacteriaceae), and sulfide-dependent chemolithoautotrophy (e.g., Sulfurovaceae) were enriched and active in less disturbed samples. These findings are supported by insights from nine deeply sequenced metagenomes and 169 derived metagenome-assembled genomes. Altogether, these findings suggest that hydrodynamic disturbance is a critical factor controlling microbial community assembly and biogeochemical processes in coastal sediments. Moreover, they strengthen our understanding of the relationships between microbial composition and biogeochemical processes in these unique environments.
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Greening C, Islam ZF, Bay SK. Hydrogen is a major lifeline for aerobic bacteria. Trends Microbiol 2021; 30:330-337. [PMID: 34462186 DOI: 10.1016/j.tim.2021.08.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 08/06/2021] [Accepted: 08/09/2021] [Indexed: 12/31/2022]
Abstract
Molecular hydrogen (H2) is available in trace amounts in most ecosystems through atmospheric, biological, geochemical, and anthropogenic sources. Aerobic bacteria use this energy-dense gas, including at atmospheric concentrations, to support respiration and carbon fixation. While it was thought that aerobic H2 consumers are rare community members, here we summarize evidence suggesting that they are dominant throughout soils and other aerated ecosystems. Bacterial cultures from at least eight major phyla can consume atmospheric H2. At the ecosystem scale, H2 consumers are abundant, diverse, and active across diverse soils and are key primary producers in extreme environments such as hyper-arid deserts. On this basis, we propose that H2 is a universally available energy source for the survival of aerobic bacteria.
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Affiliation(s)
- Chris Greening
- Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia; Securing Antarctica's Environmental Future, Monash University, Clayton, VIC 3800, Australia; Centre to Impact AMR, Monash University, Clayton, VIC 3800, Australia.
| | - Zahra F Islam
- Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia; STEM College, RMIT University, Bundoora, VIC 3083, Australia
| | - Sean K Bay
- Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia; Securing Antarctica's Environmental Future, Monash University, Clayton, VIC 3800, Australia; School of Biological Sciences, Monash University, Clayton, VIC 3800, Australia
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Mohapatra M, Yadav R, Rajput V, Dharne MS, Rastogi G. Metagenomic analysis reveals genetic insights on biogeochemical cycling, xenobiotic degradation, and stress resistance in mudflat microbiome. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 292:112738. [PMID: 34020306 DOI: 10.1016/j.jenvman.2021.112738] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 04/05/2021] [Accepted: 04/29/2021] [Indexed: 05/22/2023]
Abstract
Mudflats are highly productive coastal ecosystems that are dominated by halophytic vegetation. In this study, the mudflat sediment microbiome was investigated from Nalabana Island, located in a brackish water coastal wetland of India; Chilika, based on the MinION shotgun metagenomic analysis. Bacterial, archaeal, and fungal communities were mostly composed of Proteobacteria (38.3%), Actinobacteria (20.7%), Euryarchaeota (76.1%), Candidatus Bathyarchaeota (6.8%), Ascomycota (47.2%), and Basidiomycota (22.0%). Bacterial and archaeal community composition differed significantly between vegetated mudflat and un-vegetated bulk sediments. Carbon, nitrogen, sulfur metabolisms, oxidative phosphorylation, and xenobiotic biodegradation were the most common microbial functionalities in the mudflat metagenomes. Furthermore, genes involved in oxidative stresses, osmotolerance, secondary metabolite synthesis, and extracellular polymeric substance synthesis revealed adaptive mechanisms of the microbiome in mudflat habitat. Mudflat metagenome also revealed genes involved in the plant growth and development, suggesting that microbial communities could aid halophytic vegetation by providing tolerance to the abiotic stresses in a harsh mudflat environment. Canonical correspondence analysis and co-occurrence network revealed that both biotic (vegetation and microbial interactions) and abiotic factors played important role in shaping the mudflat microbiome composition. Among abiotic factors, pH accounted for the highest variance (20.10%) followed by available phosphorus (19.73%), total organic carbon (9.94%), salinity (8.28%), sediment texture (sand) (6.37%) and available nitrogen (5.53%) in the mudflat microbial communities. Overall, this first metagenomic study provided a comprehensive insight on the community structure, potential ecological interactions, and genetic potential of the mudflat microbiome in context to the cycling of organic matter, xenobiotic biodegradation, stress resistance, and in providing the ecological fitness to halophytes. These ecosystem services of the mudflat microbiome must be considered in the conservation and management plan of coastal wetlands. This study also advanced our understanding of fungal diversity which is understudied from the coastal lagoon ecosystems.
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Affiliation(s)
- Madhusmita Mohapatra
- Wetland Research and Training Centre, Chilika Development Authority, Balugaon, 752030, Odisha, India; School of Biotechnology, KIIT University, Bhubaneswar, Odisha, 751024, India
| | - Rakeshkumar Yadav
- National Collection of Industrial Microorganisms (NCIM), Biochemical Sciences, CSIR-National Chemical Laboratory (NCL), Pune, 411008, India; Academic of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Vinay Rajput
- National Collection of Industrial Microorganisms (NCIM), Biochemical Sciences, CSIR-National Chemical Laboratory (NCL), Pune, 411008, India
| | - Mahesh S Dharne
- National Collection of Industrial Microorganisms (NCIM), Biochemical Sciences, CSIR-National Chemical Laboratory (NCL), Pune, 411008, India; Academic of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Gurdeep Rastogi
- Wetland Research and Training Centre, Chilika Development Authority, Balugaon, 752030, Odisha, India.
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Cezar RM, Vezzani FM, Kaschuk G, Balsanelli E, de Souza EM, Vargas LK, Molin R. Crop rotation reduces the frequency of anaerobic soil bacteria in Red Latosol of Brazil. Braz J Microbiol 2021; 52:2169-2177. [PMID: 34319574 DOI: 10.1007/s42770-021-00578-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Accepted: 07/11/2021] [Indexed: 10/20/2022] Open
Abstract
Crop diversity affects the processes of soil physical structuring and most likely provokes changes in the frequencies of soil microbial communities. The study was conducted for soil prokaryotic diversity sequencing 16S rDNA genes from a 25-year no-tillage experiment comprised of two crop systems: crop succession (Triticum aestivum-Glycine max) and rotation (Vicia sativa-Zea mays-Avena sativa-Glycine max-Triticum aestivum-Glycine max). The hypothesis was that a crop system with higher crop diversification (rotation) would affect the frequencies of prokaryotic taxa against a less diverse crop system (succession) altering the major soil functions guided by bacterial diversity. Soils in both crop systems were dominated by Proteobacteria (31%), Acidobacteria (23%), Actinobacteria (10%), and Gemmatimonadetes (7.2%), among other common copiotrophic soil bacteria. Crop systems did not affect the richness and diversity indexes of soil bacteria and soil archaea. However, the crop rotation system reduced only the frequencies of anaerobic metabolism bacteria Chloroacidobacteria, Holophagae, Spirochaetes, Euryarchaeota, and Crenarchaeota. It can be concluded that crop succession, a system that is poorer in root diversity over time, may have conditioned the soil to lower oxygen diffusion and built up ecological niches that suitable for anaerobic bacteria tolerating lower levels of oxygen. On the other hand, it appeared that crop rotation has restructured the soil over the years while enabling copiotrophic aerobic bacteria to dominate the soil ecosystem. The changes prompted by crop succession have implications for efficient soil organic matter decomposition, reduced greenhouse gas emissions, higher root activity, and overall soil productivity, which compromise to agriculture sustainability.
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Affiliation(s)
- Raul Matias Cezar
- Post-Graduate in Soil Science, Federal University of Paraná, Rua Dos Funcionários, 1540, Curitiba, PR, CEP 80035-050, Brazil
| | - Fabiane Machado Vezzani
- Post-Graduate in Soil Science, Federal University of Paraná, Rua Dos Funcionários, 1540, Curitiba, PR, CEP 80035-050, Brazil
| | - Glaciela Kaschuk
- Post-Graduate in Soil Science, Federal University of Paraná, Rua Dos Funcionários, 1540, Curitiba, PR, CEP 80035-050, Brazil.
| | - Eduardo Balsanelli
- Department of Biochemistry, Federal University of Paraná, Rua Francisco H. Dos Santos S/N, Curitiba, PR, CEP 81531-990, Brazil
| | - Emanuel Maltempi de Souza
- Department of Biochemistry, Federal University of Paraná, Rua Francisco H. Dos Santos S/N, Curitiba, PR, CEP 81531-990, Brazil
| | - Luciano Kayser Vargas
- Department of Agricultural Diagnosis and Research, Secretary of Agriculture and Livestock of the State of Rio Grande Do Sul, Rua Gonçalves Dias, 570, Porto Alegre, RS, CEP 90130-060, Brazil
| | - Rudimar Molin
- ABC Foundation, Rod. PR 151 km 288, Caixa-postal: 1003, Castro, PR, CEP 84165-700, Brazil
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29
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Termite gas emissions select for hydrogenotrophic microbial communities in termite mounds. Proc Natl Acad Sci U S A 2021; 118:2102625118. [PMID: 34285074 DOI: 10.1073/pnas.2102625118] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Organoheterotrophs are the dominant bacteria in most soils worldwide. While many of these bacteria can subsist on atmospheric hydrogen (H2), levels of this gas are generally insufficient to sustain hydrogenotrophic growth. In contrast, bacteria residing within soil-derived termite mounds are exposed to high fluxes of H2 due to fermentative production within termite guts. Here, we show through community, metagenomic, and biogeochemical profiling that termite emissions select for a community dominated by diverse hydrogenotrophic Actinobacteriota and Dormibacterota. Based on metagenomic short reads and derived genomes, uptake hydrogenase and chemosynthetic RuBisCO genes were significantly enriched in mounds compared to surrounding soils. In situ and ex situ measurements confirmed that high- and low-affinity H2-oxidizing bacteria were highly active in the mounds, such that they efficiently consumed all termite-derived H2 emissions and served as net sinks of atmospheric H2 Concordant findings were observed across the mounds of three different Australian termite species, with termite activity strongly predicting H2 oxidation rates (R 2 = 0.82). Cell-specific power calculations confirmed the potential for hydrogenotrophic growth in the mounds with most termite activity. In contrast, while methane is produced at similar rates to H2 by termites, mounds contained few methanotrophs and were net sources of methane. Altogether, these findings provide further evidence of a highly responsive terrestrial sink for H2 but not methane and suggest H2 availability shapes composition and activity of microbial communities. They also reveal a unique arthropod-bacteria interaction dependent on H2 transfer between host-associated and free-living microbial communities.
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30
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Zhao R, Biddle JF. Helarchaeota and co-occurring sulfate-reducing bacteria in subseafloor sediments from the Costa Rica Margin. ISME COMMUNICATIONS 2021; 1:25. [PMID: 36737514 PMCID: PMC9723726 DOI: 10.1038/s43705-021-00027-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 05/11/2021] [Accepted: 05/26/2021] [Indexed: 02/07/2023]
Abstract
Deep sediments host many archaeal lineages, including the Asgard superphylum which contains lineages predicted to require syntrophic partnerships. Our knowledge about sedimentary archaeal diversity and their metabolic pathways and syntrophic partners is still very limited. We present here new genomes of Helarchaeota and the co-occurring sulfate-reducing bacteria (SRB) recovered from organic-rich sediments off Costa Rica Margin. Phylogenetic analyses revealed three new metagenome-assembled genomes (MAGs) affiliating with Helarchaeota, each of which has three variants of the methyl-CoM reductase-like (MCR-like) complex that may enable them to oxidize short-chain alkanes anaerobically. These Helarchaeota have no multi-heme cytochromes but have Group 3b and Group 3c [NiFe] hydrogenases, and formate dehydrogenase, and therefore have the capacity to transfer the reducing equivalents (in the forms of hydrogen and formate) generated from alkane oxidation to external partners. We also recovered five MAGs of SRB affiliated with the class of Desulfobacteria, two of which showed relative abundances (represented by genome coverages) positively correlated with those of the three Helarchaeota. Genome analysis suggested that these SRB bacteria have the capacity of H2 and formate utilization and could facilitate electron transfers from other organisms by means of these reduced substances. Their co-occurrence and metabolic features suggest that Helarchaeota may metabolize synergistically with some SRB, and together exert an important influence on the carbon cycle by mitigating the hydrocarbon emission from sediments to the overlying ocean.
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Affiliation(s)
- Rui Zhao
- School of Marine Science and Policy, University of Delaware, Lewes, DE, USA
| | - Jennifer F Biddle
- School of Marine Science and Policy, University of Delaware, Lewes, DE, USA.
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31
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Wasmund K, Pelikan C, Schintlmeister A, Wagner M, Watzka M, Richter A, Bhatnagar S, Noel A, Hubert CRJ, Rattei T, Hofmann T, Hausmann B, Herbold CW, Loy A. Genomic insights into diverse bacterial taxa that degrade extracellular DNA in marine sediments. Nat Microbiol 2021; 6:885-898. [PMID: 34127845 PMCID: PMC8289736 DOI: 10.1038/s41564-021-00917-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Accepted: 05/07/2021] [Indexed: 12/13/2022]
Abstract
Extracellular DNA is a major macromolecule in global element cycles, and is a particularly crucial phosphorus, nitrogen and carbon source for microorganisms in the seafloor. Nevertheless, the identities, ecophysiology and genetic features of DNA-foraging microorganisms in marine sediments are largely unknown. Here, we combined microcosm experiments, DNA stable isotope probing (SIP), single-cell SIP using nano-scale secondary isotope mass spectrometry (NanoSIMS) and genome-centric metagenomics to study microbial catabolism of DNA and its subcomponents in marine sediments. 13C-DNA added to sediment microcosms was largely degraded within 10 d and mineralized to 13CO2. SIP probing of DNA revealed diverse ‘Candidatus Izemoplasma’, Lutibacter, Shewanella and Fusibacteraceae incorporated DNA-derived 13C-carbon. NanoSIMS confirmed incorporation of 13C into individual bacterial cells of Fusibacteraceae sorted from microcosms. Genomes of the 13C-labelled taxa all encoded enzymatic repertoires for catabolism of DNA or subcomponents of DNA. Comparative genomics indicated that diverse ‘Candidatus Izemoplasmatales’ (former Tenericutes) are exceptional because they encode multiple (up to five) predicted extracellular nucleases and are probably specialized DNA-degraders. Analyses of additional sediment metagenomes revealed extracellular nuclease genes are prevalent among Bacteroidota at diverse sites. Together, our results reveal the identities and functional properties of microorganisms that may contribute to the key ecosystem function of degrading and recycling DNA in the seabed. Using microcosms, stable isotope probing, genome-resolved metagenomics and NanoSIMS, the authors identify diverse bacterial taxa that can degrade extracellular DNA in marine sediments, including ‘Candidatus Izemoplasma’, which encode numerous extracellular nucleases.
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Affiliation(s)
- Kenneth Wasmund
- Division of Microbial Ecology, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria. .,Austrian Polar Research Institute, Vienna, Austria. .,Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark.
| | - Claus Pelikan
- Division of Microbial Ecology, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria.,Austrian Polar Research Institute, Vienna, Austria
| | - Arno Schintlmeister
- Division of Microbial Ecology, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria.,Large-Instrument Facility for Environmental and Isotope Mass Spectrometry, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
| | - Michael Wagner
- Division of Microbial Ecology, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria.,Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark.,Large-Instrument Facility for Environmental and Isotope Mass Spectrometry, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
| | - Margarete Watzka
- Division of Terrestrial Ecosystem Research, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
| | - Andreas Richter
- Austrian Polar Research Institute, Vienna, Austria.,Division of Terrestrial Ecosystem Research, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
| | - Srijak Bhatnagar
- Geomicrobiology Group, Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada
| | - Amy Noel
- Geomicrobiology Group, Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada
| | - Casey R J Hubert
- Geomicrobiology Group, Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada
| | - Thomas Rattei
- Division of Computational Systems Biology, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
| | - Thilo Hofmann
- Division of Environmental Geosciences, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
| | - Bela Hausmann
- Joint Microbiome Facility of the Medical University of Vienna and the University of Vienna, Vienna, Austria.,Department of Laboratory Medicine, Medical University of Vienna, Vienna, Austria
| | - Craig W Herbold
- Division of Microbial Ecology, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
| | - Alexander Loy
- Division of Microbial Ecology, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria.,Austrian Polar Research Institute, Vienna, Austria.,Joint Microbiome Facility of the Medical University of Vienna and the University of Vienna, Vienna, Austria
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32
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Shi M, Zhao Y, Zhang A, Zhao M, Zhai W, Wei Z, Song Y, Tang X, He P. Factoring distinct materials and nitrogen-related microbes into assessments of nitrogen pollution risks during composting. BIORESOURCE TECHNOLOGY 2021; 329:124896. [PMID: 33657502 DOI: 10.1016/j.biortech.2021.124896] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 02/17/2021] [Accepted: 02/20/2021] [Indexed: 06/12/2023]
Abstract
The aim of this study was to evaluate nitrogen pollution risks from distinct materials composting with the discrepancy of component, including chicken manure, municipal solid and straw waste (CM, MSW, SW). Results showed total nitrogen maximum mean concentrations were observed in CM (39.57 g/kg). Pollution risks in CM were continuous, while MSW and SW mainly concentrated during heating phases. Microbial analysis confirmed that pollution risks from ammonification and nitrification were more prevalent in CM. The risks of pollution caused by nitrate reduction accompanied N2O were the most serious in MSW. The multifunctional nitrogen-related microbes Pseudomonas and Bacillus were affected by microenvironments and contributed to different pollution risks. Furthermore, PICRUSt analysis identified the "inferred" key genes (pmoC-amoC, nrfH, nifD etc.) related to nitrogen pollution risks. This study evaluated nitrogen pollution risks and proposed the future directions, providing theoretical basis and feasible optimization measures for the mitigation of nitrogen pollution during composting.
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Affiliation(s)
- Mingzi Shi
- College of Life Science, Northeast Agricultural University, Harbin 150030, China
| | - Yue Zhao
- College of Life Science, Northeast Agricultural University, Harbin 150030, China
| | - An Zhang
- College of Life Science, Northeast Agricultural University, Harbin 150030, China
| | - Maoyuan Zhao
- College of Life Science, Northeast Agricultural University, Harbin 150030, China
| | - Wenhao Zhai
- College of Life Science, Northeast Agricultural University, Harbin 150030, China
| | - Zimin Wei
- College of Life Science, Northeast Agricultural University, Harbin 150030, China.
| | - Yangyang Song
- College of Life Science, Northeast Agricultural University, Harbin 150030, China
| | - Xiaofei Tang
- Heilongjiang Province Environmental Science Research Institute, Harbin 150056, China
| | - Pingping He
- Heilongjiang Province Environmental Science Research Institute, Harbin 150056, China
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Zeng S, Sun J, Chen Z, Xu Q, Wei W, Wang D, Ni BJ. The impact and fate of clarithromycin in anaerobic digestion of waste activated sludge for biogas production. ENVIRONMENTAL RESEARCH 2021; 195:110792. [PMID: 33545126 DOI: 10.1016/j.envres.2021.110792] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2020] [Revised: 01/03/2021] [Accepted: 01/13/2021] [Indexed: 06/12/2023]
Abstract
Clarithromycin retained in waste activated sludge (WAS) inevitably enters the anaerobic digestion system. So far, the complex impacts and fate of clarithromycin in continuous operated WAS anaerobic digestion system are still unclear. In this study, two semi-continuous long-term reactors were set up to investigate the effect of clarithromycin on biogas production and antibiotic resistance genes (ARGs) during WAS anaerobic digestion, and a batch test was carried out to explore the potential metabolic mechanism. Experimental results showed that clarithromycin at lower concentrations (i.e., 0.1 and 1.0 mg/L) did not affect biogas production, whereas the decrease in biogas production was observed when the concentration of clarithromycin was further increased to 10 mg/L. Correspondingly, the relative abundance of functional bacteria in WAS anaerobic digestion (i.e., Anaerolineaceae and Microtrichales) was reduced with long-term clarithromycin exposure. The investigation of ARGs suggested that the effect of methylation belonging to the target site modification played a critical role for the anaerobic microorganisms in the expression of antibiotic resistance, and ermF, played dominated ARGs, presented the most remarkable proliferation. In comparison, the role of efflux pump was weakened with a significant decrease of two detected efflux genes. During WAS anaerobic digestion, clarithromycin could be partially degraded into metabolites with lower antimicrobial activity including oleandomycin and 5-O-desosaminyl-6-O-methylerythronolide and other metabolites without antimicrobial activity.
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Affiliation(s)
- Shuting Zeng
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China
| | - Jing Sun
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China
| | - Ziwei Chen
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China
| | - Qiuxiang Xu
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China.
| | - Wei Wei
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China
| | - Dongbo Wang
- Key Laboratory of Environmental Biology and Pollution Control, College of Environmental Science and Engineering, Hunan University, Changsha, 410082, China
| | - Bing-Jie Ni
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China.
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Taş N, de Jong AE, Li Y, Trubl G, Xue Y, Dove NC. Metagenomic tools in microbial ecology research. Curr Opin Biotechnol 2021; 67:184-191. [PMID: 33592536 DOI: 10.1016/j.copbio.2021.01.019] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 01/22/2021] [Accepted: 01/24/2021] [Indexed: 01/05/2023]
Abstract
Ability to directly sequence DNA from the environment permanently changed microbial ecology. Here, we review the new insights to microbial life gleaned from the applications of metagenomics, as well as the extensive set of analytical tools that facilitate exploration of diversity and function of complex microbial communities. While metagenomics is shaping our understanding of microbial functions in ecosystems via gene-centric and genome-centric methods, annotating functions, metagenome assembly and binning in heterogeneous samples remains challenging. Development of new analysis and sequencing platforms generating high-throughput long-read sequences and functional screening opportunities will aid in harnessing metagenomes to increase our understanding of microbial taxonomy, function, ecology, and evolution in the environment.
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Affiliation(s)
- Neslihan Taş
- Earth and Environmental Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; Biosciences Area, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
| | - Anniek Ee de Jong
- Deltares, Daltonlaan 600, 3584 BK Utrecht, The Netherlands; Department of Microbiology, Institute for Water and Wetland Research, Radboud University, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands
| | - Yaoming Li
- School of Grassland Science, Beijing Forest University, Beijing, 100083, China; Zhejiang Tiantong Forest Ecosystem National Observation and Research Station, Shanghai, 200241, China
| | - Gareth Trubl
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA 94550, USA
| | - Yaxin Xue
- Computational Biology Unit, Department of Informatics, University of Bergen, Bergen, N-5008, Norway
| | - Nicholas C Dove
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
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35
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Dong X, Rattray JE, Campbell DC, Webb J, Chakraborty A, Adebayo O, Matthews S, Li C, Fowler M, Morrison NM, MacDonald A, Groves RA, Lewis IA, Wang SH, Mayumi D, Greening C, Hubert CRJ. Thermogenic hydrocarbon biodegradation by diverse depth-stratified microbial populations at a Scotian Basin cold seep. Nat Commun 2020; 11:5825. [PMID: 33203858 PMCID: PMC7673041 DOI: 10.1038/s41467-020-19648-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 10/06/2020] [Indexed: 11/08/2022] Open
Abstract
At marine cold seeps, gaseous and liquid hydrocarbons migrate from deep subsurface origins to the sediment-water interface. Cold seep sediments are known to host taxonomically diverse microorganisms, but little is known about their metabolic potential and depth distribution in relation to hydrocarbon and electron acceptor availability. Here we combined geophysical, geochemical, metagenomic and metabolomic measurements to profile microbial activities at a newly discovered cold seep in the deep sea. Metagenomic profiling revealed compositional and functional differentiation between near-surface sediments and deeper subsurface layers. In both sulfate-rich and sulfate-depleted depths, various archaeal and bacterial community members are actively oxidizing thermogenic hydrocarbons anaerobically. Depth distributions of hydrocarbon-oxidizing archaea revealed that they are not necessarily associated with sulfate reduction, which is especially surprising for anaerobic ethane and butane oxidizers. Overall, these findings link subseafloor microbiomes to various biochemical mechanisms for the anaerobic degradation of deeply-sourced thermogenic hydrocarbons.
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Affiliation(s)
- Xiyang Dong
- School of Marine Sciences, Sun Yat-Sen University, Zhuhai, 519082, China.
- Department of Biological Sciences, University of Calgary, Calgary, AB, T2N 1N4, Canada.
| | - Jayne E Rattray
- Department of Biological Sciences, University of Calgary, Calgary, AB, T2N 1N4, Canada
| | - D Calvin Campbell
- Geological Survey of Canada-Atlantic, Dartmouth, NS, B3B 1A6, Canada
| | - Jamie Webb
- Applied Petroleum Technology (Canada), Calgary, AB, T2N 1Z6, Canada
| | - Anirban Chakraborty
- Department of Biological Sciences, University of Calgary, Calgary, AB, T2N 1N4, Canada
| | - Oyeboade Adebayo
- Department of Biological Sciences, University of Calgary, Calgary, AB, T2N 1N4, Canada
| | - Stuart Matthews
- Department of Biological Sciences, University of Calgary, Calgary, AB, T2N 1N4, Canada
| | - Carmen Li
- Department of Biological Sciences, University of Calgary, Calgary, AB, T2N 1N4, Canada
| | - Martin Fowler
- Applied Petroleum Technology (Canada), Calgary, AB, T2N 1Z6, Canada
| | - Natasha M Morrison
- Nova Scotia Department of Energy and Mines, Halifax, NS, B2Y 4A2, Canada
| | - Adam MacDonald
- Nova Scotia Department of Energy and Mines, Halifax, NS, B2Y 4A2, Canada
| | - Ryan A Groves
- Department of Biological Sciences, University of Calgary, Calgary, AB, T2N 1N4, Canada
| | - Ian A Lewis
- Department of Biological Sciences, University of Calgary, Calgary, AB, T2N 1N4, Canada
| | - Scott H Wang
- Department of Biological Sciences, University of Calgary, Calgary, AB, T2N 1N4, Canada
| | - Daisuke Mayumi
- Institute for Geo-Resources and Environment, Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba, 305-8567, Japan
| | - Chris Greening
- School of Biological Sciences, Monash University, Clayton, VIC, 3800, Australia
- Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, VIC, 3800, Australia
| | - Casey R J Hubert
- Department of Biological Sciences, University of Calgary, Calgary, AB, T2N 1N4, Canada.
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Buongiorno J, Sipes K, Wasmund K, Loy A, Lloyd KG. Woeseiales transcriptional response to shallow burial in Arctic fjord surface sediment. PLoS One 2020; 15:e0234839. [PMID: 32853201 PMCID: PMC7451513 DOI: 10.1371/journal.pone.0234839] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 08/04/2020] [Indexed: 11/30/2022] Open
Abstract
Distinct lineages of Gammaproteobacteria clade Woeseiales are globally distributed in marine sediments, based on metagenomic and 16S rRNA gene analysis. Yet little is known about why they are dominant or their ecological role in Arctic fjord sediments, where glacial retreat is rapidly imposing change. This study combined 16S rRNA gene analysis, metagenome-assembled genomes (MAGs), and genome-resolved metatranscriptomics uncovered the in situ abundance and transcriptional activity of Woeseiales with burial in four shallow sediment sites of Kongsfjorden and Van Keulenfjorden of Svalbard (79°N). We present five novel Woeseiales MAGs and show transcriptional evidence for metabolic plasticity during burial, including sulfur oxidation with reverse dissimilatory sulfite reductase (dsrAB) down to 4 cm depth and nitrite reduction down to 6 cm depth. A single stress protein, spore protein SP21 (hspA), had a tenfold higher mRNA abundance than any other transcript, and was a hundredfold higher on average than other transcripts. At three out of the four sites, SP21 transcript abundance increased with depth, while total mRNA abundance and richness decreased, indicating a shift in investment from metabolism and other cellular processes to build-up of spore protein SP21. The SP21 gene in MAGs was often flanked by genes involved in membrane-associated stress response. The ability of Woeseiales to shift from sulfur oxidation to nitrite reduction with burial into marine sediments with decreasing access to overlying oxic bottom waters, as well as enter into a dormant state dominated by SP21, may account for its ubiquity and high abundance in marine sediments worldwide, including those of the rapidly shifting Arctic.
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Affiliation(s)
- Joy Buongiorno
- Department of Microbiology, University of Tennessee, Knoxville, Tennessee, United States of America
| | - Katie Sipes
- Department of Microbiology, University of Tennessee, Knoxville, Tennessee, United States of America
| | - Kenneth Wasmund
- Division of Microbial Ecology, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
- Austrian Polar Research Institute, Vienna, Austria
| | - Alexander Loy
- Division of Microbial Ecology, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
- Austrian Polar Research Institute, Vienna, Austria
| | - Karen G. Lloyd
- Department of Microbiology, University of Tennessee, Knoxville, Tennessee, United States of America
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A widely distributed hydrogenase oxidises atmospheric H 2 during bacterial growth. ISME JOURNAL 2020; 14:2649-2658. [PMID: 32647310 PMCID: PMC7784904 DOI: 10.1038/s41396-020-0713-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 06/25/2020] [Accepted: 06/30/2020] [Indexed: 11/09/2022]
Abstract
Diverse aerobic bacteria persist by consuming atmospheric hydrogen (H2) using group 1h [NiFe]-hydrogenases. However, other hydrogenase classes are also distributed in aerobes, including the group 2a [NiFe]-hydrogenase. Based on studies focused on Cyanobacteria, the reported physiological role of the group 2a [NiFe]-hydrogenase is to recycle H2 produced by nitrogenase. However, given this hydrogenase is also present in various heterotrophs and lithoautotrophs lacking nitrogenases, it may play a wider role in bacterial metabolism. Here we investigated the role of this enzyme in three species from different phylogenetic lineages and ecological niches: Acidithiobacillus ferrooxidans (phylum Proteobacteria), Chloroflexus aggregans (phylum Chloroflexota), and Gemmatimonas aurantiaca (phylum Gemmatimonadota). qRT-PCR analysis revealed that the group 2a [NiFe]-hydrogenase of all three species is significantly upregulated during exponential growth compared to stationary phase, in contrast to the profile of the persistence-linked group 1h [NiFe]-hydrogenase. Whole-cell biochemical assays confirmed that all three strains aerobically respire H2 to sub-atmospheric levels, and oxidation rates were much higher during growth. Moreover, the oxidation of H2 supported mixotrophic growth of the carbon-fixing strains C. aggregans and A. ferrooxidans. Finally, we used phylogenomic analyses to show that this hydrogenase is widely distributed and is encoded by 13 bacterial phyla. These findings challenge the current persistence-centric model of the physiological role of atmospheric H2 oxidation and extend this process to two more phyla, Proteobacteria and Gemmatimonadota. In turn, these findings have broader relevance for understanding how bacteria conserve energy in different environments and control the biogeochemical cycling of atmospheric trace gases.
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38
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Macrofaunal control of microbial community structure in continental margin sediments. Proc Natl Acad Sci U S A 2020; 117:15911-15922. [PMID: 32576690 PMCID: PMC7376573 DOI: 10.1073/pnas.1917494117] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Through a process called "bioturbation," burrowing macrofauna have altered the seafloor habitat and modified global carbon cycling since the Cambrian. However, the impact of macrofauna on the community structure of microorganisms is poorly understood. Here, we show that microbial communities across bioturbated, but geochemically and sedimentologically divergent, continental margin sites are highly similar but differ clearly from those in nonbioturbated surface and underlying subsurface sediments. Solid- and solute-phase geochemical analyses combined with modeled bioturbation activities reveal that dissolved O2 introduction by burrow ventilation is the major driver of archaeal community structure. By contrast, solid-phase reworking, which regulates the distribution of fresh, algal organic matter, is the main control of bacterial community structure. In nonbioturbated surface sediments and in subsurface sediments, bacterial and archaeal communities are more divergent between locations and appear mainly driven by site-specific differences in organic carbon sources.
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39
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Benoit SL, Maier RJ, Sawers RG, Greening C. Molecular Hydrogen Metabolism: a Widespread Trait of Pathogenic Bacteria and Protists. Microbiol Mol Biol Rev 2020; 84:e00092-19. [PMID: 31996394 PMCID: PMC7167206 DOI: 10.1128/mmbr.00092-19] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Pathogenic microorganisms use various mechanisms to conserve energy in host tissues and environmental reservoirs. One widespread but often overlooked means of energy conservation is through the consumption or production of molecular hydrogen (H2). Here, we comprehensively review the distribution, biochemistry, and physiology of H2 metabolism in pathogens. Over 200 pathogens and pathobionts carry genes for hydrogenases, the enzymes responsible for H2 oxidation and/or production. Furthermore, at least 46 of these species have been experimentally shown to consume or produce H2 Several major human pathogens use the large amounts of H2 produced by colonic microbiota as an energy source for aerobic or anaerobic respiration. This process has been shown to be critical for growth and virulence of the gastrointestinal bacteria Salmonella enterica serovar Typhimurium, Campylobacter jejuni, Campylobacter concisus, and Helicobacter pylori (including carcinogenic strains). H2 oxidation is generally a facultative trait controlled by central regulators in response to energy and oxidant availability. Other bacterial and protist pathogens produce H2 as a diffusible end product of fermentation processes. These include facultative anaerobes such as Escherichia coli, S Typhimurium, and Giardia intestinalis, which persist by fermentation when limited for respiratory electron acceptors, as well as obligate anaerobes, such as Clostridium perfringens, Clostridioides difficile, and Trichomonas vaginalis, that produce large amounts of H2 during growth. Overall, there is a rich literature on hydrogenases in growth, survival, and virulence in some pathogens. However, we lack a detailed understanding of H2 metabolism in most pathogens, especially obligately anaerobic bacteria, as well as a holistic understanding of gastrointestinal H2 transactions overall. Based on these findings, we also evaluate H2 metabolism as a possible target for drug development or other therapies.
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Affiliation(s)
- Stéphane L Benoit
- Department of Microbiology, University of Georgia, Athens, Georgia, USA
| | - Robert J Maier
- Department of Microbiology, University of Georgia, Athens, Georgia, USA
| | - R Gary Sawers
- Institute of Microbiology, Martin Luther University Halle-Wittenberg, Halle, Germany
| | - Chris Greening
- School of Biological Sciences, Monash University, Clayton, VIC, Australia
- Department of Microbiology, Monash Biomedicine Discovery Institute, Clayton, VIC, Australia
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40
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Greening C, Boyd E. Editorial: Microbial Hydrogen Metabolism. Front Microbiol 2020; 11:56. [PMID: 32082284 PMCID: PMC7002543 DOI: 10.3389/fmicb.2020.00056] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 01/13/2020] [Indexed: 11/14/2022] Open
Affiliation(s)
- Chris Greening
- School of Biological Sciences, Monash University, Clayton, VIC, Australia
| | - Eric Boyd
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, United States
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41
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Islam ZF, Cordero PRF, Greening C. Putative Iron-Sulfur Proteins Are Required for Hydrogen Consumption and Enhance Survival of Mycobacteria. Front Microbiol 2019; 10:2749. [PMID: 31824474 PMCID: PMC6883350 DOI: 10.3389/fmicb.2019.02749] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Accepted: 11/12/2019] [Indexed: 01/01/2023] Open
Abstract
Aerobic soil bacteria persist by scavenging molecular hydrogen (H2) from the atmosphere. This key process is the primary sink in the biogeochemical hydrogen cycle and supports the productivity of oligotrophic ecosystems. In Mycobacterium smegmatis, atmospheric H2 oxidation is catalyzed by two phylogenetically distinct [NiFe]-hydrogenases, Huc (group 2a) and Hhy (group 1h). However, it is currently unresolved how these enzymes transfer electrons derived from H2 oxidation into the aerobic respiratory chain. In this work, we used genetic approaches to confirm that two putative iron-sulfur cluster proteins encoded on the hydrogenase structural operons, HucE and HhyE, are required for H2 consumption in M. smegmatis. Sequence analysis show that these proteins, while homologous, fall into distinct phylogenetic clades and have distinct metal-binding motifs. H2 oxidation was reduced when the genes encoding these proteins were deleted individually and was eliminated when they were deleted in combination. In turn, the growth yield and long-term survival of these deletion strains was modestly but significantly reduced compared to the parent strain. In both biochemical and phenotypic assays, the mutant strains lacking the putative iron-sulfur proteins phenocopied those of hydrogenase structural subunit mutants. We hypothesize that these proteins mediate electron transfer between the catalytic subunits of the hydrogenases and the menaquinone pool of the M. smegmatis respiratory chain; however, other roles (e.g., in maturation) are also plausible and further work is required to resolve their role. The conserved nature of these proteins within most Hhy- or Huc-encoding organisms suggests that these proteins are important determinants of atmospheric H2 oxidation.
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Affiliation(s)
| | | | - Chris Greening
- School of Biological Sciences, Monash University, Clayton, VIC, Australia
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Yu T, Zhang M, Kang D, Zhao S, Ding A, Lin Q, Xu D, Hong Y, Wang L, Zheng P. Characteristics of Microbial Communities and Their Correlation With Environmental Substrates and Sediment Type in the Gas-Bearing Formation of Hangzhou Bay, China. Front Microbiol 2019; 10:2421. [PMID: 31708895 PMCID: PMC6819322 DOI: 10.3389/fmicb.2019.02421] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 10/07/2019] [Indexed: 12/02/2022] Open
Abstract
Shallow gas is a kind of natural gas buried in shallow strata, generally, with methane as the main component, endowing it a potential energy resource while also a potential risk to the safety of ground engineering and environment. Microbial activity is usually regarded as an important driving force to generate shallow gas via metabolizing the environmental substrates. Therefore, the research on the microbial communities will be helpful to reveal the distribution of shallow gas in the gas-bearing formation. In this study, 30 sediment samples below the seabed in Hangzhou Bay (China) from depths of 1.5 m to 55 m were collected to investigate their microbial community, environmental characteristics and sediment type (clay or sand). It turned out that the presence of shallow gas had a good correlation with the distribution of archaea rather than bacteria, with the dominant microbe of Bathyarchaeota, Thaumarchaeota, and Euryarchaeota in the formation. Methanosarcinaceae and ANME-1a with the capacity of methane metabolism occupied high proportions. The correlation analysis and redundancy analysis (RDA) suggested that ammonium was a key environmental substrate to indicate the microbial community in the formation. The sediment type was proposed to shape environmental substrates in the formation, thus further affecting the microbial communities. The clay strata were demonstrated to have an important role in the generation and distribution of shallow gas, and more attention should be paid in terms of its resource discovery and engineering safety assessment.
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Affiliation(s)
- Tao Yu
- Department of Environmental Engineering, College of Environmental & Resource Sciences, Zhejiang University, Hangzhou, China
| | - Meng Zhang
- Department of Environmental Engineering, College of Environmental & Resource Sciences, Zhejiang University, Hangzhou, China
- Advanced Environmental Biotechnology Centre, Nanyang Environment & Water Research Institute, Nanyang Technological University, Singapore, Singapore
| | - Da Kang
- Department of Environmental Engineering, College of Environmental & Resource Sciences, Zhejiang University, Hangzhou, China
| | - Shuang Zhao
- Key Laboratory of Offshore Geotechnics and Material of Zhejiang Province, College of Civil Engineering and Architecture, Zhejiang University, Hangzhou, China
| | - Aqiang Ding
- Department of Environmental Science, College of Resources and Environmental Science, Chongqing University, Chongqing, China
| | - Qiujian Lin
- Department of Environmental Engineering, College of Environmental & Resource Sciences, Zhejiang University, Hangzhou, China
| | - Dongdong Xu
- Department of Environmental Engineering, College of Environmental & Resource Sciences, Zhejiang University, Hangzhou, China
| | - Yi Hong
- Key Laboratory of Offshore Geotechnics and Material of Zhejiang Province, College of Civil Engineering and Architecture, Zhejiang University, Hangzhou, China
| | - Lizhong Wang
- Key Laboratory of Offshore Geotechnics and Material of Zhejiang Province, College of Civil Engineering and Architecture, Zhejiang University, Hangzhou, China
| | - Ping Zheng
- Department of Environmental Engineering, College of Environmental & Resource Sciences, Zhejiang University, Hangzhou, China
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43
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Cordero PRF, Grinter R, Hards K, Cryle MJ, Warr CG, Cook GM, Greening C. Two uptake hydrogenases differentially interact with the aerobic respiratory chain during mycobacterial growth and persistence. J Biol Chem 2019; 294:18980-18991. [PMID: 31624148 DOI: 10.1074/jbc.ra119.011076] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 10/12/2019] [Indexed: 12/11/2022] Open
Abstract
To persist when nutrient sources are limited, aerobic soil bacteria metabolize atmospheric hydrogen (H2). This process is the primary sink in the global H2 cycle and supports the productivity of microbes in oligotrophic environments. H2-metabolizing bacteria possess [NiFe] hydrogenases that oxidize H2 to subatmospheric concentrations. The soil saprophyte Mycobacterium smegmatis has two such [NiFe] hydrogenases, designated Huc and Hhy, that belong to different phylogenetic subgroups. Both Huc and Hhy are oxygen-tolerant, oxidize H2 to subatmospheric concentrations, and enhance bacterial survival during hypoxia and carbon limitation. Why does M. smegmatis require two hydrogenases with a seemingly similar function? In this work, we resolved this question by showing that Huc and Hhy are differentially expressed, localized, and integrated into the respiratory chain. Huc is active in late exponential and early stationary phases, supporting energy conservation during mixotrophic growth and transition into dormancy. In contrast, Hhy is most active during long-term persistence, providing energy for maintenance processes following carbon exhaustion. We also show that Huc and Hhy are obligately linked to the aerobic respiratory chain via the menaquinone pool and are differentially affected by respiratory uncouplers. Consistently, these two enzymes interacted differentially with the respiratory terminal oxidases. Huc exclusively donated electrons to, and possibly physically associated with, the proton-pumping cytochrome bcc-aa 3 supercomplex. In contrast the more promiscuous Hhy also provided electrons to the cytochrome bd oxidase complex. These results indicate that, despite their similar characteristics, Huc and Hhy perform distinct functions during mycobacterial growth and survival.
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Affiliation(s)
- Paul R F Cordero
- School of Biological Sciences, Monash University, Clayton, VIC 3800, Australia
| | - Rhys Grinter
- School of Biological Sciences, Monash University, Clayton, VIC 3800, Australia
| | - Kiel Hards
- Department of Microbiology and Immunology, University of Otago, Dunedin, OTA 9016, New Zealand
| | - Max J Cryle
- Monash Biomedicine Discovery Institute, Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia
| | - Coral G Warr
- School of Biological Sciences, Monash University, Clayton, VIC 3800, Australia.,School of Medicine, University of Tasmania, Hobart, TAS 7000, Australia
| | - Gregory M Cook
- Department of Microbiology and Immunology, University of Otago, Dunedin, OTA 9016, New Zealand
| | - Chris Greening
- School of Biological Sciences, Monash University, Clayton, VIC 3800, Australia
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44
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Greening C, Geier R, Wang C, Woods LC, Morales SE, McDonald MJ, Rushton-Green R, Morgan XC, Koike S, Leahy SC, Kelly WJ, Cann I, Attwood GT, Cook GM, Mackie RI. Diverse hydrogen production and consumption pathways influence methane production in ruminants. ISME JOURNAL 2019; 13:2617-2632. [PMID: 31243332 PMCID: PMC6776011 DOI: 10.1038/s41396-019-0464-2] [Citation(s) in RCA: 102] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Revised: 06/03/2019] [Accepted: 06/07/2019] [Indexed: 01/17/2023]
Abstract
Farmed ruminants are the largest source of anthropogenic methane emissions globally. The methanogenic archaea responsible for these emissions use molecular hydrogen (H2), produced during bacterial and eukaryotic carbohydrate fermentation, as their primary energy source. In this work, we used comparative genomic, metatranscriptomic and co-culture-based approaches to gain a system-wide understanding of the organisms and pathways responsible for ruminal H2 metabolism. Two-thirds of sequenced rumen bacterial and archaeal genomes encode enzymes that catalyse H2 production or consumption, including 26 distinct hydrogenase subgroups. Metatranscriptomic analysis confirmed that these hydrogenases are differentially expressed in sheep rumen. Electron-bifurcating [FeFe]-hydrogenases from carbohydrate-fermenting Clostridia (e.g., Ruminococcus) accounted for half of all hydrogenase transcripts. Various H2 uptake pathways were also expressed, including methanogenesis (Methanobrevibacter), fumarate and nitrite reduction (Selenomonas), and acetogenesis (Blautia). Whereas methanogenesis-related transcripts predominated in high methane yield sheep, alternative uptake pathways were significantly upregulated in low methane yield sheep. Complementing these findings, we observed significant differential expression and activity of the hydrogenases of the hydrogenogenic cellulose fermenter Ruminococcus albus and the hydrogenotrophic fumarate reducer Wolinella succinogenes in co-culture compared with pure culture. We conclude that H2 metabolism is a more complex and widespread trait among rumen microorganisms than previously recognised. There is evidence that alternative hydrogenotrophs, including acetogenic and respiratory bacteria, can prosper in the rumen and effectively compete with methanogens for H2. These findings may help to inform ongoing strategies to mitigate methane emissions by increasing flux through alternative H2 uptake pathways, including through animal selection, dietary supplementation and methanogenesis inhibitors.
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Affiliation(s)
- Chris Greening
- School of Biological Sciences, Monash University, Clayton, VIC, 3800, Australia.
| | - Renae Geier
- Department of Animal Sciences and Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Cecilia Wang
- Department of Microbiology and Immunology, University of Otago, Dunedin, 9016, New Zealand
| | - Laura C Woods
- School of Biological Sciences, Monash University, Clayton, VIC, 3800, Australia
| | - Sergio E Morales
- Department of Microbiology and Immunology, University of Otago, Dunedin, 9016, New Zealand
| | - Michael J McDonald
- School of Biological Sciences, Monash University, Clayton, VIC, 3800, Australia
| | - Rowena Rushton-Green
- Department of Microbiology and Immunology, University of Otago, Dunedin, 9016, New Zealand
| | - Xochitl C Morgan
- Department of Microbiology and Immunology, University of Otago, Dunedin, 9016, New Zealand
| | - Satoshi Koike
- Research Faculty of Agriculture, Hokkaido University, Sapporo, Japan
| | - Sinead C Leahy
- Grasslands Research Centre, AgResearch Ltd., Palmerston North, 4410, New Zealand
| | | | - Isaac Cann
- Department of Animal Sciences and Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Graeme T Attwood
- Grasslands Research Centre, AgResearch Ltd., Palmerston North, 4410, New Zealand
| | - Gregory M Cook
- Department of Microbiology and Immunology, University of Otago, Dunedin, 9016, New Zealand
| | - Roderick I Mackie
- Department of Animal Sciences and Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
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Novotnik B, Zorz J, Bryant S, Strous M. The Effect of Dissimilatory Manganese Reduction on Lactate Fermentation and Microbial Community Assembly. Front Microbiol 2019; 10:1007. [PMID: 31156573 PMCID: PMC6531920 DOI: 10.3389/fmicb.2019.01007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Accepted: 04/18/2019] [Indexed: 12/30/2022] Open
Abstract
Fermentation and dissimilatory manganese (Mn) reduction are inter-related metabolic processes that microbes can perform in anoxic environments. Fermentation is less energetically favorable and is often not considered to compete for organic carbon with dissimilatory metal reduction. Therefore, the aim of our study was to investigate the outcome of the competition for lactate between fermentation and Mn oxide (birnessite) reduction in a mixed microbial community. A birnessite reducing enrichment culture was obtained from activated sludge with lactate and birnessite as the substrates. This enrichment was further used to test how various birnessite activities (0, 10, 20, and 40 mM) affected the rates of fermentation and metal reduction, as well as community composition. Increased birnessite activity led to a decrease of lactate consumption rate. Acetate and propionate were the main products. With increasing birnessite activity, the propionate/acetate ratio decreased from 1.4 to 0.47. Significant CO2 production was detected only in the absence of birnessite. In its presence, CO2 concentrations remained close to the background since most of the CO2 produced in these experiments was recovered as MnCO3. The Mn reduction efficiency (Mn(II) produced divided by birnessite added) was the highest at 10 mM birnessite added, where about 50% of added birnessite was reduced to Mn(II), whereas at 20 and 40 mM approximately 21 and 16% was reduced. The decreased birnessite reduction efficiency at higher birnessite activities points to inhibition by terminal electron acceptors and/or its toxicity which was also indicated by retarded lactate oxidation and decreased concentrations of microbial metabolites. Birnessite activity strongly affected microbial community structure. Firmicutes and Bacteroidetes were the most abundant phyla at 0 mM of birnessite. Their abundance was inversely correlated with birnessite concentration. The relative sequence abundance of Proteobacteria correlated with birnessite concentrations. Most of the enriched populations were involved in lactate/acetate or amino acid fermentation and the only previously known metal reducing genus detected was related to Shewanella sp. The sequencing data confirmed that lactate consumption coupled to metal reduction was only one of the processes occurring and did not outcompete fermentation processes.
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Affiliation(s)
- Breda Novotnik
- Department of Geoscience, University of Calgary, Calgary, AB, Canada
| | - Jackie Zorz
- Department of Geoscience, University of Calgary, Calgary, AB, Canada
| | - Steven Bryant
- Department of Chemical and Petroleum Engineering, University of Calgary, Calgary, AB, Canada
| | - Marc Strous
- Department of Geoscience, University of Calgary, Calgary, AB, Canada
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Greening C, Grinter R, Chiri E. Uncovering the Metabolic Strategies of the Dormant Microbial Majority: towards Integrative Approaches. mSystems 2019; 4:e00107-19. [PMID: 31120024 PMCID: PMC6529542 DOI: 10.1128/msystems.00107-19] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Accepted: 03/11/2019] [Indexed: 11/20/2022] Open
Abstract
A grand challenge in microbiology is to understand how the dormant majority lives. In natural environments, most microorganisms are not growing and instead exist in a spectrum of dormant states. Despite this, most research on microbial metabolism continues to be growth-centric, and many overlook the fact that dormant cells require energy for maintenance. In this perspective, we discuss our research program to uncover the metabolic strategies that support microbial survival. We present two major principles underlying these studies. The first is the recent realization that microbial survival depends on previously unrecognized metabolic flexibility. The second is that new discoveries in this area depend on more sophisticated integration of approaches at the molecular, cellular, and ecosystem levels. These principles are illustrated with examples from the literature, including our own work demonstrating that bacteria can live on air, and areas for future methodological and theoretical development are highlighted.
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Affiliation(s)
- Chris Greening
- School of Biological Sciences, Monash University, Clayton, Victoria, Australia
| | - Rhys Grinter
- School of Biological Sciences, Monash University, Clayton, Victoria, Australia
| | - Eleonora Chiri
- School of Biological Sciences, Monash University, Clayton, Victoria, Australia
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