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Liu S, Zheng N, Wang J, Zhao S. Relationships among bacterial cell size, diversity, and taxonomy in rumen. Front Microbiol 2024; 15:1376994. [PMID: 38628864 PMCID: PMC11018980 DOI: 10.3389/fmicb.2024.1376994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Accepted: 03/07/2024] [Indexed: 04/19/2024] Open
Abstract
Introduction The rumen microbial community plays a crucial role in the digestion and metabolic processes of ruminants. Although sequencing-based studies have helped reveal the diversity and functions of bacteria in the rumen, their physiological and biochemical characteristics, as well as their dynamic regulation along the digestion process in the rumen, remain poorly understood. Addressing these gaps requires pure culture studies to demystify the intricate mechanisms at play. Bacteria exhibit morphological differentiation associated with different species. Based on the difference in size or shape of microorganisms, size fractionation by filters with various pore sizes can be used to separate them. Methods In this study, we used polyvinylidene difluoride filters with pore sizes of 300, 120, 80, 40, 20, 8, 6, 2.1, and 0.6 μm. Bacterial suspensions were successively passed through these filters for the analysis of microbial population distribution using 16S rRNA gene sequences. Results We found that bacteria from the different pore sizes were clustered into four branches (> 120 μm, 40-120 μm, 6-20 μm, 20-40 μm, and < 0.6 μm), indicating that size fractionation had effects on enriching specific groups but could not effectively separate dominant groups by cell size alone. The species of unclassified Flavobacterium, unclassified Chryseobacterium, unclassified Delftia, Methylotenera mobilis, unclassified Caulobacteraceae, unclassified Oligella, unclassified Sphingomonas, unclassified Stenotrophomonas, unclassified Shuttleworthia, unclassified Sutterella, unclassified Alphaproteobacteria, and unclassified SR1 can be efficiently enriched or separated by size fractionation. Discussion In this study, we investigated the diversity of sorted bacteria populations in the rumen for preliminary investigations of the relationship between the size and classification of rumen bacteria that have the potential to improve our ability to isolate and culture bacteria from the rumen in the future.
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Affiliation(s)
- Sijia Liu
- College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, China
- State Key Laboratory of Animal Nutrition and Feeding, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Nan Zheng
- State Key Laboratory of Animal Nutrition and Feeding, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Jiaqi Wang
- State Key Laboratory of Animal Nutrition and Feeding, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Shengguo Zhao
- State Key Laboratory of Animal Nutrition and Feeding, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
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2
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Benito Merino D, Lipp JS, Borrel G, Boetius A, Wegener G. Anaerobic hexadecane degradation by a thermophilic Hadarchaeon from Guaymas Basin. THE ISME JOURNAL 2024; 18:wrad004. [PMID: 38365230 PMCID: PMC10811742 DOI: 10.1093/ismejo/wrad004] [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: 10/25/2023] [Accepted: 11/06/2023] [Indexed: 02/18/2024]
Abstract
Hadarchaeota inhabit subsurface and hydrothermally heated environments, but previous to this study, they had not been cultured. Based on metagenome-assembled genomes, most Hadarchaeota are heterotrophs that grow on sugars and amino acids, or oxidize carbon monoxide or reduce nitrite to ammonium. A few other metagenome-assembled genomes encode alkyl-coenzyme M reductases (Acrs), β-oxidation, and Wood-Ljungdahl pathways, pointing toward multicarbon alkane metabolism. To identify the organisms involved in thermophilic oil degradation, we established anaerobic sulfate-reducing hexadecane-degrading cultures from hydrothermally heated sediments of the Guaymas Basin. Cultures at 70°C were enriched in one Hadarchaeon that we propose as Candidatus Cerberiarchaeum oleivorans. Genomic and chemical analyses indicate that Ca. C. oleivorans uses an Acr to activate hexadecane to hexadecyl-coenzyme M. A β-oxidation pathway and a tetrahydromethanopterin methyl branch Wood-Ljungdahl (mWL) pathway allow the complete oxidation of hexadecane to CO2. Our results suggest a syntrophic lifestyle with sulfate reducers, as Ca. C. oleivorans lacks a sulfate respiration pathway. Comparative genomics show that Acr, mWL, and β-oxidation are restricted to one family of Hadarchaeota, which we propose as Ca. Cerberiarchaeaceae. Phylogenetic analyses further indicate that the mWL pathway is basal to all Hadarchaeota. By contrast, the carbon monoxide dehydrogenase/acetyl-coenzyme A synthase complex in Ca. Cerberiarchaeaceae was horizontally acquired from Bathyarchaeia. The Acr and β-oxidation genes of Ca. Cerberiarchaeaceae are highly similar to those of other alkane-oxidizing archaea such as Ca. Methanoliparia and Ca. Helarchaeales. Our results support the use of Acrs in the degradation of petroleum alkanes and suggest a role of Hadarchaeota in oil-rich environments.
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Affiliation(s)
- David Benito Merino
- Max Planck Institute for Marine Microbiology, Celsiusstraße 1, 28359, Bremen, Germany
- Faculty of Geosciences, University of Bremen, Klagenfurter Straße 2, 428359, Bremen, Germany
| | - Julius S Lipp
- MARUM, Center for Marine Environmental Sciences, University of Bremen, Leobener Straße 8, 28359, Bremen, Germany
| | - Guillaume Borrel
- Department of Microbiology, Unit Evolutionary Biology of the Microbial Cell, Institut Pasteur, 25 rue du Dr Roux, 75015, Paris, France
| | - Antje Boetius
- Max Planck Institute for Marine Microbiology, Celsiusstraße 1, 28359, Bremen, Germany
- MARUM, Center for Marine Environmental Sciences, University of Bremen, Leobener Straße 8, 28359, Bremen, Germany
- Alfred Wegener Institute Helmholtz Center for Polar and Marine Research, Am Handelshafen 12, 27570, Bremerhaven, Germany
| | - Gunter Wegener
- Max Planck Institute for Marine Microbiology, Celsiusstraße 1, 28359, Bremen, Germany
- MARUM, Center for Marine Environmental Sciences, University of Bremen, Leobener Straße 8, 28359, Bremen, Germany
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3
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Duan C, Liu Y, Liu Y, Liu L, Cai M, Zhang R, Zeng Q, Koonin EV, Krupovic M, Li M. Diversity of Bathyarchaeia viruses in metagenomes and virus-encoded CRISPR system components. ISME COMMUNICATIONS 2024; 4:ycad011. [PMID: 38328448 PMCID: PMC10848311 DOI: 10.1093/ismeco/ycad011] [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: 12/03/2023] [Revised: 12/14/2023] [Accepted: 12/18/2023] [Indexed: 02/09/2024]
Abstract
Bathyarchaeia represent a class of archaea common and abundant in sedimentary ecosystems. Here we report 56 metagenome-assembled genomes of Bathyarchaeia viruses identified in metagenomes from different environments. Gene sharing network and phylogenomic analyses led to the proposal of four virus families, including viruses of the realms Duplodnaviria and Adnaviria, and archaea-specific spindle-shaped viruses. Genomic analyses uncovered diverse CRISPR elements in these viruses. Viruses of the proposed family "Fuxiviridae" harbor an atypical Type IV-B CRISPR-Cas system and a Cas4 protein that might interfere with host immunity. Viruses of the family "Chiyouviridae" encode a Cas2-like endonuclease and two mini-CRISPR arrays, one with a repeat identical to that in the host CRISPR array, potentially allowing the virus to recruit the host CRISPR adaptation machinery to acquire spacers that could contribute to competition with other mobile genetic elements or to inhibit host defenses. These findings present an outline of the Bathyarchaeia virome and offer a glimpse into their counter-defense mechanisms.
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Affiliation(s)
- Changhai Duan
- SZU-HKUST Joint PhD Program in Marine Environmental Science, Shenzhen University, Shenzhen 518060, China
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China
- Department of Ocean Science, The Hong Kong University of Science and Technology, Hong Kong 999077, China
| | - Yang Liu
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China
| | - Ying Liu
- Institut Pasteur, Université Paris Cité, Archaeal Virology Unit, Paris 75015, France
| | - Lirui Liu
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China
| | - Mingwei Cai
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China
| | - Rui Zhang
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China
| | - Qinglu Zeng
- Department of Ocean Science, The Hong Kong University of Science and Technology, Hong Kong 999077, China
| | - Eugene V Koonin
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA
| | - Mart Krupovic
- Institut Pasteur, Université Paris Cité, Archaeal Virology Unit, Paris 75015, France
| | - Meng Li
- SZU-HKUST Joint PhD Program in Marine Environmental Science, Shenzhen University, Shenzhen 518060, China
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China
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4
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Verrone V, Gupta A, Laloo AE, Dubey RK, Hamid NAA, Swarup S. Organic matter stability and lability in terrestrial and aquatic ecosystems: A chemical and microbial perspective. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 906:167757. [PMID: 37852479 DOI: 10.1016/j.scitotenv.2023.167757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 10/06/2023] [Accepted: 10/10/2023] [Indexed: 10/20/2023]
Abstract
Terrestrial and aquatic ecosystems have specific carbon fingerprints and sequestration potential, due to the intrinsic properties of the organic matter (OM), mineral content, environmental conditions, and microbial community composition and functions. A small variation in the OM pool can imbalance the carbon dynamics that ultimately affect the climate and functionality of each ecosystem, at regional and global scales. Here, we review the factors that continuously contribute to carbon stability and lability, with particular attention to the OM formation and nature, as well as the microbial activities that drive OM aggregation, degradation and eventually greenhouse gas emissions. We identified that in both aquatic and terrestrial ecosystems, microbial attributes (i.e., carbon metabolism, carbon use efficiency, necromass, enzymatic activities) play a pivotal role in transforming the carbon stock and yet they are far from being completely characterised and not often included in carbon estimations. Therefore, future research must focus on the integration of microbial components into carbon mapping and models, as well as on translating molecular-scaled studies into practical approaches. These strategies will improve carbon management and restoration across ecosystems and contribute to overcome current climate challenges.
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Affiliation(s)
- Valeria Verrone
- National University of Singapore Environmental Research Institute, National University of Singapore,117411, Singapore
| | - Abhishek Gupta
- Singapore Centre of Environmental Engineering and Life Sciences, National University of Singapore, Singapore.
| | - Andrew Elohim Laloo
- National University of Singapore Environmental Research Institute, National University of Singapore,117411, Singapore; Singapore Centre of Environmental Engineering and Life Sciences, National University of Singapore, Singapore
| | - Rama Kant Dubey
- National University of Singapore Environmental Research Institute, National University of Singapore,117411, Singapore; Department of Biological Sciences, National University of Singapore, Singapore 117558, Singapore; Department of Biotechnology, GLA University, Mathura, Uttar Pradesh 281406, India
| | - Nur Ashikin Abdul Hamid
- National University of Singapore Environmental Research Institute, National University of Singapore,117411, Singapore
| | - Sanjay Swarup
- National University of Singapore Environmental Research Institute, National University of Singapore,117411, Singapore; Singapore Centre of Environmental Engineering and Life Sciences, National University of Singapore, Singapore; Department of Biological Sciences, National University of Singapore, Singapore 117558, Singapore
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Liu J, Li C, Ma W, Wu Z, Liu W, Wu W. Exploitation alters microbial community and its co-occurrence patterns in ionic rare earth mining sites. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 898:165532. [PMID: 37454857 DOI: 10.1016/j.scitotenv.2023.165532] [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: 03/30/2023] [Revised: 06/29/2023] [Accepted: 07/12/2023] [Indexed: 07/18/2023]
Abstract
The exploitation of ion-adsorption rare earth elements (REEs) deposits results in serious ecological and environmental problems, which has attracted much attention. However, the influences of exploitation on the prokaryotic communities and their complex interactions remain poorly understood. In the present study, bacterial and archaeal communities, as well as ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA), in and around REEs mining area were investigated through high throughput sequencing and quantitative polymerase chain reaction (qPCR). Our results indicated that mining soil was characterized by poor soil structure, nutrient deficiency, and high concentrations of residual REEs. Oligotrophic bacteria (e.g., Chloroflexi and Acidobacteriota) were dominant in unexploited soil and mining soil, while copiotrophic bacteria (Proteobacteria and Actinobacteriota) were more abundant in surrounding soil. Nutrient was the key factor affecting microbial variation and abundance in mining soil. The bacterial community was more sensitive to REEs, while the archaeal communities were relatively stable. As the key members for ammonia oxidation, AOA outnumbered AOB in all the soil types, and the former was significantly influenced by pH, nutrients, and TREEs in mining soil. The microbial co-occurrence network analysis demonstrated that exploitation significantly influenced topological properties, decreased the complexity, and resulted in a much unstable network, leading to a more fragile microbial ecosystem in mining areas. Notably, the abundance of keystone taxa decreased after exploitation, and oligotrophic groups (Chloroflexi) replaced copiotrophic groups (Proteobacteria and Actinobacteriota) as the key to rebuilt a co-occurrence network, suggesting potentially important roles in maintaining network stability. The current results are of great significance to the ecological risk assessment of REEs exploitation.
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Affiliation(s)
- Jingjing Liu
- School of Energy and Machinery Engineering, Jiangxi University of Science and Technology, Nanchang 330013, China; Jiangxi Key Laboratory of Mining & Metallurgy Environmental Pollution Control, Ganzhou 341099, China.
| | - Chun Li
- School of Energy and Machinery Engineering, Jiangxi University of Science and Technology, Nanchang 330013, China
| | - Wendan Ma
- School of Energy and Machinery Engineering, Jiangxi University of Science and Technology, Nanchang 330013, China
| | - Zengxue Wu
- School of Energy and Machinery Engineering, Jiangxi University of Science and Technology, Nanchang 330013, China
| | - Wei Liu
- College of Chemistry and Environmental Science, Hebei University, Baoding 071002, China
| | - Weixiang Wu
- Institute of Environmental Science and Technology, Zhejiang University, Hangzhou 310030, China
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6
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Gusmão ACB, Peres FV, Paula FS, Pellizari VH, Kolm HE, Signori CN. Microbial communities in the deep-sea sediments of the South São Paulo Plateau, Southwestern Atlantic Ocean. Int Microbiol 2023; 26:1041-1051. [PMID: 37093322 DOI: 10.1007/s10123-023-00358-w] [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: 02/14/2023] [Revised: 03/30/2023] [Accepted: 04/06/2023] [Indexed: 04/25/2023]
Abstract
Microbial communities play a key role in the ocean, acting as primary producers, nutrient recyclers, and energy providers. The São Paulo Plateau is a region located on the southeastern coast of Brazil within economic importance, due to its oil and gas reservoirs. With this focus, this study examined the diversity and composition of microbial communities in marine sediments located at three oceanographic stations in the southern region of São Paulo Plateau using the HOV Shinkai 6500 in 2013. The 16S rRNA gene was sequenced using the universal primers (515F and 926R) by the Illumina Miseq platform. The taxonomic compositions of samples recovered from SP3 station were markedly distinct from those obtained from SP1 and SP2. Although all three stations exhibited a high abundance of Gammaproteobacteria (> 15%), this taxon dominated more than 90% of composition of the A and C sediment layers at SP3. The highest abundance of the archaeal class Nitrososphaeria was presented at SP1, mainly at layer C (~ 21%), being absent at SP3 station. The prediction of chemoheterotrophy and fermentation as important microbial functions was supported by the data. Additionally, other metabolic pathways related to the cycles of nitrogen, carbon and sulfur were also predicted. The core microbiome analysis comprised only two ASVs. Our study contributes to a better understanding of microbial communities in an economically important little-explored region. This is the third microbiological survey in plateau sediments and the first focused on the southern region.
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Affiliation(s)
- Ana Carolina Bercini Gusmão
- Department of Biological Oceanography, Oceanographic Institute, University of São Paulo, Praça Do Oceanográfico, 191. CEP: 05508-120, São Paulo, Brazil.
| | - Francielli Vilela Peres
- Department of Biological Oceanography, Oceanographic Institute, University of São Paulo, Praça Do Oceanográfico, 191. CEP: 05508-120, São Paulo, Brazil
| | - Fabiana S Paula
- Department of Biological Oceanography, Oceanographic Institute, University of São Paulo, Praça Do Oceanográfico, 191. CEP: 05508-120, São Paulo, Brazil
| | - Vivian Helena Pellizari
- Department of Biological Oceanography, Oceanographic Institute, University of São Paulo, Praça Do Oceanográfico, 191. CEP: 05508-120, São Paulo, Brazil
| | - Hedda Elisabeth Kolm
- Department of Oceanography, Center for Marine Studies, Federal University of Paraná, Pontal do Paraná, Brazil
| | - Camila Negrão Signori
- Department of Biological Oceanography, Oceanographic Institute, University of São Paulo, Praça Do Oceanográfico, 191. CEP: 05508-120, São Paulo, Brazil
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Perez-Garcia P, Chow J, Costanzi E, Gurschke M, Dittrich J, Dierkes RF, Molitor R, Applegate V, Feuerriegel G, Tete P, Danso D, Thies S, Schumacher J, Pfleger C, Jaeger KE, Gohlke H, Smits SHJ, Schmitz RA, Streit WR. An archaeal lid-containing feruloyl esterase degrades polyethylene terephthalate. Commun Chem 2023; 6:193. [PMID: 37697032 PMCID: PMC10495362 DOI: 10.1038/s42004-023-00998-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Accepted: 08/31/2023] [Indexed: 09/13/2023] Open
Abstract
Polyethylene terephthalate (PET) is a commodity polymer known to globally contaminate marine and terrestrial environments. Today, around 80 bacterial and fungal PET-active enzymes (PETases) are known, originating from four bacterial and two fungal phyla. In contrast, no archaeal enzyme had been identified to degrade PET. Here we report on the structural and biochemical characterization of PET46 (RLI42440.1), an archaeal promiscuous feruloyl esterase exhibiting degradation activity on semi-crystalline PET powder comparable to IsPETase and LCC (wildtypes), and higher activity on bis-, and mono-(2-hydroxyethyl) terephthalate (BHET and MHET). The enzyme, found by a sequence-based metagenome search, is derived from a non-cultivated, deep-sea Candidatus Bathyarchaeota archaeon. Biochemical characterization demonstrated that PET46 is a promiscuous, heat-adapted hydrolase. Its crystal structure was solved at a resolution of 1.71 Å. It shares the core alpha/beta-hydrolase fold with bacterial PETases, but contains a unique lid common in feruloyl esterases, which is involved in substrate binding. Thus, our study widens the currently known diversity of PET-hydrolyzing enzymes, by demonstrating PET depolymerization by a plant cell wall-degrading esterase.
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Affiliation(s)
- Pablo Perez-Garcia
- Department of Microbiology and Biotechnology, University of Hamburg, Hamburg, Germany
- Institute for General Microbiology, Christian-Albrechts-Universität zu Kiel, Kiel, Germany
| | - Jennifer Chow
- Department of Microbiology and Biotechnology, University of Hamburg, Hamburg, Germany
| | - Elisa Costanzi
- Center for Structural Studies (CSS), Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Marno Gurschke
- Department of Microbiology and Biotechnology, University of Hamburg, Hamburg, Germany
| | - Jonas Dittrich
- Institute for Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Robert F Dierkes
- Department of Microbiology and Biotechnology, University of Hamburg, Hamburg, Germany
| | - Rebecka Molitor
- Institute of Molecular Enzyme Technology (IMET), Heinrich Heine University Düsseldorf, Jülich, Germany
| | - Violetta Applegate
- Center for Structural Studies (CSS), Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Golo Feuerriegel
- Department of Microbiology and Biotechnology, University of Hamburg, Hamburg, Germany
| | - Prince Tete
- Department of Microbiology and Biotechnology, University of Hamburg, Hamburg, Germany
| | - Dominik Danso
- Department of Microbiology and Biotechnology, University of Hamburg, Hamburg, Germany
| | - Stephan Thies
- Institute of Molecular Enzyme Technology (IMET), Heinrich Heine University Düsseldorf, Jülich, Germany
| | - Julia Schumacher
- Center for Structural Studies (CSS), Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Christopher Pfleger
- Institute for Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Karl-Erich Jaeger
- Institute of Molecular Enzyme Technology (IMET), Heinrich Heine University Düsseldorf, Jülich, Germany
- Institute of Bio- and Geosciences IBG-1: Biotechnology, Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Holger Gohlke
- Institute for Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- Institute for Bio- and Geosciences (IBG-4: Bioinformatics), Forschungszentrum Jülich, Jülich, Germany
| | - Sander H J Smits
- Center for Structural Studies (CSS), Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- Institute for Biochemistry, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Ruth A Schmitz
- Institute for General Microbiology, Christian-Albrechts-Universität zu Kiel, Kiel, Germany.
| | - Wolfgang R Streit
- Department of Microbiology and Biotechnology, University of Hamburg, Hamburg, Germany.
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Yu T, Hu H, Zeng X, Wang Y, Pan D, Deng L, Liang L, Hou J, Wang F. Widespread Bathyarchaeia encode a novel methyltransferase utilizing lignin-derived aromatics. MLIFE 2023; 2:272-282. [PMID: 38817817 PMCID: PMC10989822 DOI: 10.1002/mlf2.12082] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 06/26/2023] [Accepted: 07/12/2023] [Indexed: 06/01/2024]
Abstract
Lignin degradation is a major process in the global carbon cycle across both terrestrial and marine ecosystems. Bathyarchaeia, which are among the most abundant microorganisms in marine sediment, have been proposed to mediate anaerobic lignin degradation. However, the mechanism of bathyarchaeial lignin degradation remains unclear. Here, we report an enrichment culture of Bathyarchaeia, named Candidatus Baizosediminiarchaeum ligniniphilus DL1YTT001 (Ca. B. ligniniphilus), from coastal sediments that can grow with lignin as the sole organic carbon source under mesophilic anoxic conditions. Ca. B. ligniniphilus possesses and highly expresses novel methyltransferase 1 (MT1, mtgB) for transferring methoxyl groups from lignin monomers to cob(I)alamin. MtgBs have no homology with known microbial methyltransferases and are present only in bathyarchaeial lineages. Heterologous expression of the mtgB gene confirmed O-demethylation activity. The mtgB genes were identified in metagenomic data sets from a wide range of coastal sediments, and they were highly expressed in coastal sediments from the East China Sea. These findings suggest that Bathyarchaeia, capable of O-demethylation via their novel and specific methyltransferases, are ubiquitous in coastal sediments.
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Affiliation(s)
- Tiantian Yu
- School of OceanographyShanghai Jiao Tong UniversityShanghaiChina
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghaiChina
| | - Haining Hu
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghaiChina
| | - Xianhong Zeng
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghaiChina
| | - Yinzhao Wang
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghaiChina
| | - Donald Pan
- School of OceanographyShanghai Jiao Tong UniversityShanghaiChina
| | - Longhui Deng
- School of OceanographyShanghai Jiao Tong UniversityShanghaiChina
| | - Lewen Liang
- School of OceanographyShanghai Jiao Tong UniversityShanghaiChina
| | - Jialin Hou
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghaiChina
| | - Fengping Wang
- School of OceanographyShanghai Jiao Tong UniversityShanghaiChina
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghaiChina
- Southern Marine Science and EngineeringGuangdong Laboratory (Zhuhai)ZhuhaiChina
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9
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Duan C, Liu Y, Liu Y, Liu L, Cai M, Zhang R, Zeng Q, Koonin EV, Krupovic M, Li M. Diversity of Bathyarchaeia viruses in metagenomes and virus-encoded CRISPR system components. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.24.554615. [PMID: 37781628 PMCID: PMC10541130 DOI: 10.1101/2023.08.24.554615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/03/2023]
Abstract
Bathyarchaeia represent a class of archaea common and abundant in sedimentary ecosystems. The virome of Bathyarchaeia so far has not been characterized. Here we report 56 metagenome-assembled genomes of Bathyarchaeia viruses identified in metagenomes from different environments. Gene sharing network and phylogenomic analyses led to the proposal of four virus families, including viruses of the realms Duplodnaviria and Adnaviria, and archaea-specific spindle-shaped viruses. Genomic analyses uncovered diverse CRISPR elements in these viruses. Viruses of the proposed family 'Fuxiviridae' harbor an atypical type IV-B CRISPR-Cas system and a Cas4 protein that might interfere with host immunity. Viruses of the family 'Chiyouviridae' encode a Cas2-like endonuclease and two mini-CRISPR arrays, one with a repeat identical to that in the host CRISPR array, potentially allowing the virus to recruit the host CRISPR adaptation machinery to acquire spacers that could contribute to competition with other mobile genetic elements or to inhibition of host defenses. These findings present an outline of the Bathyarchaeia virome and offer a glimpse into their counter-defense mechanisms.
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Affiliation(s)
- Changhai Duan
- SZU-HKUST Joint PhD Program in Marine Environmental Science, Shenzhen University, 518060 Shenzhen, China
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, 518060 Shenzhen, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, 518060 Shenzhen, China
- Department of Ocean Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - Yang Liu
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, 518060 Shenzhen, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, 518060 Shenzhen, China
| | - Ying Liu
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, Archaeal Virology Unit, 75015 Paris, France
| | - Lirui Liu
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, 518060 Shenzhen, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, 518060 Shenzhen, China
| | - Mingwei Cai
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, 518060 Shenzhen, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, 518060 Shenzhen, China
| | - Rui Zhang
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, 518060 Shenzhen, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, 518060 Shenzhen, China
| | - Qinglu Zeng
- Department of Ocean Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - Eugene V Koonin
- National Center for Biotechnology Information, National Library of Medicine, Bethesda, MD 20894, USA
| | - Mart Krupovic
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, Archaeal Virology Unit, 75015 Paris, France
| | - Meng Li
- SZU-HKUST Joint PhD Program in Marine Environmental Science, Shenzhen University, 518060 Shenzhen, China
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, 518060 Shenzhen, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, 518060 Shenzhen, China
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10
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Khomyakova MA, Merkel AY, Mamiy DD, Klyukina AA, Slobodkin AI. Phenotypic and genomic characterization of Bathyarchaeum tardum gen. nov., sp. nov., a cultivated representative of the archaeal class Bathyarchaeia. Front Microbiol 2023; 14:1214631. [PMID: 37675420 PMCID: PMC10477458 DOI: 10.3389/fmicb.2023.1214631] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Accepted: 07/31/2023] [Indexed: 09/08/2023] Open
Abstract
Bathyarchaeia are widespread in various anoxic ecosystems and are considered one of the most abundant microbial groups on the earth. There are only a few reports of laboratory cultivation of Bathyarchaeia, and none of the representatives of this class has been isolated in pure culture. Here, we report a sustainable cultivation of the Bathyarchaeia archaeon (strain M17CTs) enriched from anaerobic sediment of a coastal lake. The cells of strain M17CTs were small non-motile cocci, 0.4-0.7 μm in diameter. The cytoplasmic membrane was surrounded by an S-layer and covered with an outermost electron-dense sheath. Strain M17CTs is strictly anaerobic mesophile. It grows at 10-45°C (optimum 37°C), at pH 6.0-10.0 (optimum 8.0), and at NaCl concentrations of 0-60 g l-1 (optimum 20 g l-1). Growth occurred in the presence of methoxylated aromatic compounds (3,4-dimethoxybenzoate and vanillate) together with complex proteinaceous substrates. Dimethyl sulfoxide and nitrate stimulated growth. The phylogenomic analysis placed strain M17CTs to BIN-L-1 genus-level lineage from the BA1 family-level lineage and B26-1 order-level lineage (former subgroup-8) within the class Bathyarchaeia. The complete genome of strain M17CTs had a size of 2.15 Mb with a DNA G + C content of 38.1%. Based on phylogenomic position and phenotypic and genomic properties, we propose to assign strain M17CTs to a new species of a novel genus Bathyarchaeum tardum gen. nov., sp. nov. within the class Bathyarchaeia. This is the first sustainably cultivated representative of Bathyarchaeia. We propose under SeqCode the complete genome sequence of strain M17CTs (CP122380) as a nomenclatural type of Bathyarchaeum tardum, which should be considered as a type for the genus Bathyarchaeum, which is proposed as a type for the family Bathyarchaeaceae, order Bathyarchaeales, and of the class Bathyarchaeia.
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Affiliation(s)
- Maria A. Khomyakova
- Winogradsky Institute of Microbiology, FRC Biotechnology, Russian Academy of Sciences, Moscow, Russia
| | - Alexander Y. Merkel
- Winogradsky Institute of Microbiology, FRC Biotechnology, Russian Academy of Sciences, Moscow, Russia
| | - Dana D. Mamiy
- Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Alexandra A. Klyukina
- Winogradsky Institute of Microbiology, FRC Biotechnology, Russian Academy of Sciences, Moscow, Russia
| | - Alexander I. Slobodkin
- Winogradsky Institute of Microbiology, FRC Biotechnology, Russian Academy of Sciences, Moscow, Russia
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11
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Hou J, Wang Y, Zhu P, Yang N, Liang L, Yu T, Niu M, Konhauser K, Woodcroft BJ, Wang F. Taxonomic and carbon metabolic diversification of Bathyarchaeia during its coevolution history with early Earth surface environment. SCIENCE ADVANCES 2023; 9:eadf5069. [PMID: 37406125 DOI: 10.1126/sciadv.adf5069] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2022] [Accepted: 06/01/2023] [Indexed: 07/07/2023]
Abstract
Bathyarchaeia, as one of the most abundant microorganisms on Earth, play vital roles in the global carbon cycle. However, our understanding of their origin, evolution, and ecological functions remains poorly constrained. Here, we present the largest dataset of Bathyarchaeia metagenome assembled genome to date and reclassify Bathyarchaeia into eight order-level units corresponding to the former subgroup system. Highly diversified and versatile carbon metabolisms were found among different orders, particularly atypical C1 metabolic pathways, indicating that Bathyarchaeia represent overlooked important methylotrophs. Molecular dating results indicate that Bathyarchaeia diverged at ~3.3 billion years, followed by three major diversifications at ~3.0, ~2.5, and ~1.8 to 1.7 billion years, likely driven by continental emergence, growth, and intensive submarine volcanism, respectively. The lignin-degrading Bathyarchaeia clade emerged at ~300 million years perhaps contributed to the sharply decreased carbon sequestration rate during the Late Carboniferous period. The evolutionary history of Bathyarchaeia potentially has been shaped by geological forces, which, in turn, affected Earth's surface environment.
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Affiliation(s)
- Jialin Hou
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Yinzhao Wang
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Pengfei Zhu
- School of Oceanography, Shanghai Jiao Tong University, Shanghai, China
| | - Na Yang
- School of Oceanography, Shanghai Jiao Tong University, Shanghai, China
| | - Lewen Liang
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Tiantian Yu
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Mingyang Niu
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Kurt Konhauser
- Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Ben J Woodcroft
- Centre for Microbiome Research, School of Biomedical Sciences, Queensland University of Technology (QUT), Translational Research Institute, Woolloongabba, Australia
| | - Fengping Wang
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
- School of Oceanography, Shanghai Jiao Tong University, Shanghai, China
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
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12
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Lopez-Fernandez M, Westmeijer G, Turner S, Broman E, Ståhle M, Bertilsson S, Dopson M. Thiobacillus as a key player for biofilm formation in oligotrophic groundwaters of the Fennoscandian Shield. NPJ Biofilms Microbiomes 2023; 9:41. [PMID: 37349512 DOI: 10.1038/s41522-023-00408-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2021] [Accepted: 06/09/2023] [Indexed: 06/24/2023] Open
Abstract
Biofilm formation is a common adaptation for microbes in energy-limited conditions such as those prevalent in the vast deep terrestrial biosphere. However, due to the low biomass and the inaccessible nature of subsurface groundwaters, the microbial populations and genes involved in its formation are understudied. Here, a flow-cell system was designed to investigate biofilm formation under in situ conditions in two groundwaters of contrasting age and geochemistry at the Äspö Hard Rock Laboratory, Sweden. Metatranscriptomes showed Thiobacillus, Sideroxydans, and Desulforegula to be abundant and together accounted for 31% of the transcripts in the biofilm communities. Differential expression analysis highlighted Thiobacillus to have a principal role in biofilm formation in these oligotrophic groundwaters by being involved in relevant processes such as the formation of extracellular matrix, quorum sensing, and cell motility. The findings revealed an active biofilm community with sulfur cycling as a prominent mode of energy conservation in the deep biosphere.
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Affiliation(s)
- Margarita Lopez-Fernandez
- Centre for Ecology and Evolution in Microbial Model Systems (EEMiS), Linnaeus University, Stuvaregatan 4, 392 31, Kalmar, Sweden.
- Department of Microbiology, Faculty of Sciences, University of Granada, Avenida Fuentenueva s/n, 18071, Granada, Spain.
| | - George Westmeijer
- Centre for Ecology and Evolution in Microbial Model Systems (EEMiS), Linnaeus University, Stuvaregatan 4, 392 31, Kalmar, Sweden
| | - Stephanie Turner
- Centre for Ecology and Evolution in Microbial Model Systems (EEMiS), Linnaeus University, Stuvaregatan 4, 392 31, Kalmar, Sweden
- Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences, Box 7026, 75007, Uppsala, Sweden
| | - Elias Broman
- Centre for Ecology and Evolution in Microbial Model Systems (EEMiS), Linnaeus University, Stuvaregatan 4, 392 31, Kalmar, Sweden
- Department of Ecology, Environment and Plant Sciences, Stockholm University, Svante Arrhenius väg 20 A, 106 91, Stockholm, Sweden
| | - Magnus Ståhle
- Centre for Ecology and Evolution in Microbial Model Systems (EEMiS), Linnaeus University, Stuvaregatan 4, 392 31, Kalmar, Sweden
| | - Stefan Bertilsson
- Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Box 7050, SE75007, Uppsala, Sweden
| | - Mark Dopson
- Centre for Ecology and Evolution in Microbial Model Systems (EEMiS), Linnaeus University, Stuvaregatan 4, 392 31, Kalmar, Sweden
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13
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Su L, Teske AP, MacGregor BJ, McKay LJ, Mendlovitz H, Albert D, Ma Z, Li J. Thermal Selection of Microbial Communities and Preservation of Microbial Function in Guaymas Basin Hydrothermal Sediments. Appl Environ Microbiol 2023; 89:e0001823. [PMID: 36847505 PMCID: PMC10057036 DOI: 10.1128/aem.00018-23] [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: 01/10/2023] [Accepted: 01/27/2023] [Indexed: 03/01/2023] Open
Abstract
The Guaymas Basin in the Gulf of California is characterized by active seafloor spreading, hydrothermal activity, and organic matter accumulation on the seafloor due to high sedimentation rates. In the hydrothermal sediments of Guaymas Basin, microbial community compositions and coexistence patterns change across steep gradients of temperature, potential carbon sources, and electron acceptors. Nonmetric multidimensional scaling and guanine-cytosine percentage analyses reveal that the bacterial and archaeal communities adjust compositionally to their local temperature regime. Functional inference using PICRUSt shows that microbial communities consistently maintain their predicted biogeochemical functions in different sediments. Phylogenetic profiling shows that microbial communities retain distinct sulfate-reducing, methane-oxidizing, or heterotrophic lineages within specific temperature windows. The preservation of similar biogeochemical functions across microbial lineages with different temperature adaptations stabilizes the hydrothermal microbial community in a highly dynamic environment. IMPORTANCE Hydrothermal vent sites have been widely studied to investigate novel bacteria and archaea that are adapted to these extreme environments. However, community-level analyses of hydrothermal microbial ecosystems look beyond the presence and activity of particular types of microbes and examine to what extent the entire community of bacteria and archaea is adapted to hydrothermal conditions; these include elevated temperatures, hydrothermally generated carbon sources, and inorganic electron donors and acceptors that are characteristic for hydrothermal environments. In our case study of bacterial and archaeal communities in hydrothermal sediments of Guaymas Basin, we found that sequence-inferred microbial function was maintained in differently structured bacterial and archaeal communities across different samples and thermal regimes. The resulting preservation of biogeochemical functions across thermal gradients is an important factor in explaining the consistency of the microbial core community in the dynamic sedimentary environment of Guaymas Basin.
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Affiliation(s)
- Lei Su
- State Key Laboratory of Marine Geology, Tongji University, Shanghai, China
| | - Andreas P. Teske
- Department of Marine Sciences, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Barbara J. MacGregor
- Department of Marine Sciences, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Earth Sciences, University of Minnesota, Minneapolis, Minnesota, USA
| | - Luke J. McKay
- Department of Marine Sciences, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Howard Mendlovitz
- Department of Marine Sciences, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Daniel Albert
- Department of Marine Sciences, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Zhonglin Ma
- State Key Laboratory of Marine Geology, Tongji University, Shanghai, China
| | - Jiangtao Li
- State Key Laboratory of Marine Geology, Tongji University, Shanghai, China
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14
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Seidel L, Sachpazidou V, Ketzer M, Hylander S, Forsman A, Dopson M. Long-term warming modulates diversity, vertical structuring of microbial communities, and sulfate reduction in coastal Baltic Sea sediments. Front Microbiol 2023; 14:1099445. [PMID: 37065140 PMCID: PMC10090409 DOI: 10.3389/fmicb.2023.1099445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 03/10/2023] [Indexed: 03/31/2023] Open
Abstract
Coastal waters such as those found in the Baltic Sea already suffer from anthropogenic related problems including increased algal blooming and hypoxia while ongoing and future climate change will likely worsen these effects. Microbial communities in sediments play a crucial role in the marine energy- and nutrient cycling, and how they are affected by climate change and shape the environment in the future is of great interest. The aims of this study were to investigate potential effects of prolonged warming on microbial community composition and nutrient cycling including sulfate reduction in surface (∼0.5 cm) to deeper sediments (∼ 24 cm). To investigate this, 16S rRNA gene amplicon sequencing was performed, and sulfate concentrations were measured and compared between sediments in a heated bay (which has been used as a cooling water outlet from a nearby nuclear power plant for approximately 50 years) and a nearby but unaffected control bay. The results showed variation in overall microbial diversity according to sediment depth and higher sulfate flux in the heated bay compared to the control bay. A difference in vertical community structure reflected increased relative abundances of sulfur oxidizing- and sulfate reducing bacteria along with a higher proportion of archaea, such as Bathyarchaeota, in the heated compared to the control bay. This was particularly evident closer to the sediment surface, indicating a compression of geochemical zones in the heated bay. These results corroborate findings in previous studies and additionally point to an amplified effect of prolonged warming deeper in the sediment, which could result in elevated concentrations of toxic compounds and greenhouse gases closer to the sediment surface.
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15
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Tekwa EW, Catalano KA, Bazzicalupo AL, O'Connor MI, Pinsky ML. The sizes of life. PLoS One 2023; 18:e0283020. [PMID: 36989258 PMCID: PMC10057745 DOI: 10.1371/journal.pone.0283020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Accepted: 02/28/2023] [Indexed: 03/30/2023] Open
Abstract
Recent research has revealed the diversity and biomass of life across ecosystems, but how that biomass is distributed across body sizes of all living things remains unclear. We compile the present-day global body size-biomass spectra for the terrestrial, marine, and subterranean realms. To achieve this compilation, we pair existing and updated biomass estimates with previously uncatalogued body size ranges across all free-living biological groups. These data show that many biological groups share similar ranges of body sizes, and no single group dominates size ranges where cumulative biomass is highest. We then propagate biomass and size uncertainties and provide statistical descriptions of body size-biomass spectra across and within major habitat realms. Power laws show exponentially decreasing abundance (exponent -0.9±0.02 S.D., R2 = 0.97) and nearly equal biomass (exponent 0.09±0.01, R2 = 0.56) across log size bins, which resemble previous aquatic size spectra results but with greater organismal inclusivity and global coverage. In contrast, a bimodal Gaussian mixture model describes the biomass pattern better (R2 = 0.86) and suggests small (~10-15 g) and large (~107 g) organisms outweigh other sizes by one order magnitude (15 and 65 Gt versus ~1 Gt per log size). The results suggest that the global body size-biomass relationships is bimodal, but substantial one-to-two orders-of-magnitude uncertainty mean that additional data will be needed to clarify whether global-scale universal constraints or local forces shape these patterns.
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Affiliation(s)
- Eden W Tekwa
- Department of Zoology, University of British Columbia, Vancouver, BC, Canada
- Department of Ecology, Evolution and Natural Resources, Rutgers University, New Brunswick, NJ, United States of America
| | - Katrina A Catalano
- Department of Ecology, Evolution and Natural Resources, Rutgers University, New Brunswick, NJ, United States of America
| | - Anna L Bazzicalupo
- Department of Zoology, University of British Columbia, Vancouver, BC, Canada
| | - Mary I O'Connor
- Department of Zoology, University of British Columbia, Vancouver, BC, Canada
| | - Malin L Pinsky
- Department of Ecology, Evolution and Natural Resources, Rutgers University, New Brunswick, NJ, United States of America
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16
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Lazar CS, Schmidt F, Elvert M, Heuer VB, Hinrichs KU, Teske AP. Microbial diversity gradients in the geothermal mud volcano underlying the hypersaline Urania Basin. Front Microbiol 2022; 13:1043414. [PMID: 36620052 PMCID: PMC9812581 DOI: 10.3389/fmicb.2022.1043414] [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: 09/13/2022] [Accepted: 12/01/2022] [Indexed: 12/24/2022] Open
Abstract
Mud volcanoes transport deep fluidized sediment and their microbial communities and thus provide a window into the deep biosphere. However, mud volcanoes are commonly sampled at the surface and not probed at greater depths, with the consequence that their internal geochemistry and microbiology remain hidden from view. Urania Basin, a hypersaline seafloor basin in the Mediterranean, harbors a mud volcano that erupts fluidized mud into the brine. The vertical mud pipe was amenable to shipboard Niskin bottle and multicorer sampling and provided an opportunity to investigate the downward sequence of bacterial and archaeal communities of the Urania Basin brine, fluid mud layers and consolidated subsurface sediments using 16S rRNA gene sequencing. These microbial communities show characteristic, habitat-related trends as they change throughout the sample series, from extremely halophilic bacteria (KB1) and archaea (Halodesulfoarchaeum spp.) in the brine, toward moderately halophilic and thermophilic endospore-forming bacteria and uncultured archaeal lineages in the mud fluid, and finally ending in aromatics-oxidizing bacteria, uncultured spore formers, and heterotrophic subsurface archaea (Thermoplasmatales, Bathyarchaeota, and Lokiarcheota) in the deep subsurface sediment at the bottom of the mud volcano. Since these bacterial and archaeal lineages are mostly anaerobic heterotrophic fermenters, the microbial ecosystem in the brine and fluidized mud functions as a layered fermenter for the degradation of sedimentary biomass and hydrocarbons. By spreading spore-forming, thermophilic Firmicutes during eruptions, the Urania Basin mud volcano likely functions as a source of endospores that occur widely in cold seafloor sediments.
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Affiliation(s)
- Cassandre Sara Lazar
- Department of Biological Sciences, Université du Québec à Montréal, Montréal, QC, Canada
| | - Frauke Schmidt
- Organic Geochemistry Group, Department of Geosciences, MARUM Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | - Marcus Elvert
- Organic Geochemistry Group, Department of Geosciences, MARUM Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | - Verena B. Heuer
- Organic Geochemistry Group, Department of Geosciences, MARUM Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | - Kai-Uwe Hinrichs
- Organic Geochemistry Group, Department of Geosciences, MARUM Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | - Andreas P. Teske
- Department of Earth, Marine and Environmental Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
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17
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Gong X, Chen Z, Deng Y, Zhao D, Gao P, Zhang L, Tu Q, Qu L, Zheng L, Zhang Y, Song C, Liu J. Contrasting archaeal and bacterial community assembly processes and the importance of rare taxa along a depth gradient in shallow coastal sediments. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 852:158411. [PMID: 36055486 DOI: 10.1016/j.scitotenv.2022.158411] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 08/18/2022] [Accepted: 08/26/2022] [Indexed: 06/15/2023]
Abstract
Marine microbial communities assemble along a sediment depth gradient and are responsible for processing organic matter. Composition of the microbial community along the depth is affected by various biotic and abiotic factors, e.g., the change of redox gradient, the availability of organic matter, and the interactions of different taxa. The community structure is also subjected to some random changes caused by stochastic processes of birth, death, immigration and emigration. However, the high-resolution shifts of microbial community and mechanisms of the vertical assembly processes in marine sediments remain poorly described. Archaeal and bacterial communities were analyzed based on 16S rRNA gene amplicon sequencing and metagenomes in the Bohai Sea sediment samples. The archaeal community was dominated by Thaumarchaeota with increased alpha diversity along depth. Proteobacteria was the dominant bacterial group with decreased alpha diversity as depth increased. Sampling sites and depths collectively affected the beta-diversity for both archaeal and bacterial communities. The dominant mechanism determining archaeal community assembly was determinism, which was mostly contributed by homogeneous selection, i.e., consistent selection pressures in different locations or depths. In contrast, bacterial community assembly was dominated by stochasticity. Co-occurrence networks among different taxa and key functional genes revealed a tight community with low modularity in the bottom sediment, and disproportionately more interactions among low abundant ASVs. This suggests a significant contribution to community stabilization by rare taxa, and suggests that the bottom layer, rather than surface sediments may represent a hotspot for benthic microbial interactions.
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Affiliation(s)
- Xianzhe Gong
- Institute of Marine Science and Technology, Shandong University, Qingdao, Shandong 266237, China; Marine Science Institute, University of Texas at Austin, Port Aransas, TX 78373, USA.
| | - Zhiyi Chen
- Institute of Marine Science and Technology, Shandong University, Qingdao, Shandong 266237, China; State Key Laboratory of Microbial Technology, Shandong University, Qingdao, Shandong 266237, China
| | - Ye Deng
- Institute of Marine Science and Technology, Shandong University, Qingdao, Shandong 266237, China; CAS Key Laboratory for Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences (CAS), Beijing 100085, China
| | - Duo Zhao
- Institute of Marine Science and Technology, Shandong University, Qingdao, Shandong 266237, China
| | - Ping Gao
- First Institute of Oceanography, Ministry of Natural Resources, Qingdao 266237, China
| | - Liang Zhang
- Advanced Environmental Biotechnology Center, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore 637141, Singapore
| | - Qichao Tu
- Institute of Marine Science and Technology, Shandong University, Qingdao, Shandong 266237, China
| | - Lingyun Qu
- First Institute of Oceanography, Ministry of Natural Resources, Qingdao 266237, China
| | - Liwen Zheng
- Institute of Marine Science and Technology, Shandong University, Qingdao, Shandong 266237, China
| | - Yong Zhang
- Institute of Marine Science and Technology, Shandong University, Qingdao, Shandong 266237, China
| | - Chao Song
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, China
| | - Jihua Liu
- Institute of Marine Science and Technology, Shandong University, Qingdao, Shandong 266237, China.
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18
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Zhang X, Zhang C, Liu Y, Zhang R, Li M. Non-negligible roles of archaea in coastal carbon biogeochemical cycling. Trends Microbiol 2022; 31:586-600. [PMID: 36567186 DOI: 10.1016/j.tim.2022.11.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2022] [Revised: 11/16/2022] [Accepted: 11/18/2022] [Indexed: 12/25/2022]
Abstract
Coastal zones are among the world's most productive ecosystems. They store vast amounts of organic carbon, as 'blue carbon' reservoirs, and impact global climate change. Archaeal communities are integral components of coastal microbiomes but their ecological roles are often overlooked. However, archaeal diversity, metabolism, evolution, and interactions, revealed by recent studies using rapidly developing cutting-edge technologies, place archaea as important players in coastal carbon biogeochemical cycling. We here summarize the latest advances in the understanding of archaeal carbon cycling processes in coastal ecosystems, specifically, archaeal involvement in CO2 fixation, organic biopolymer transformation, and methane metabolism. We also showcase the potential to use of archaeal communities to increase carbon sequestration and reduce methane production, with implications for mitigating climate change.
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Affiliation(s)
- Xinxu Zhang
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, Shenzhen, Guangdong, China; Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, Guangdong, China
| | - Cuijing Zhang
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, Shenzhen, Guangdong, China; Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, Guangdong, China
| | - Yang Liu
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, Shenzhen, Guangdong, China; Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, Guangdong, China
| | - Rui Zhang
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, Shenzhen, Guangdong, China; Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, Guangdong, China
| | - Meng Li
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, Shenzhen, Guangdong, China; Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, Guangdong, China.
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19
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Zou D, Li H, Du P, Wang B, Lin H, Liu H, Chen J, Li M. Distinct Features of Sedimentary Archaeal Communities in Hypoxia and Non-Hypoxia Regions off the Changjiang River Estuary. Microbiol Spectr 2022; 10:e0194722. [PMID: 36066619 PMCID: PMC9602602 DOI: 10.1128/spectrum.01947-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 08/12/2022] [Indexed: 12/31/2022] Open
Abstract
Water hypoxia (DO < 2 mg/L) is a growing global environmental concern that has the potential to significantly influence not only the aquatic ecosystem but also the benthic sedimentary ecosystem. The Changjiang River Estuary hypoxia, classified as one of the world's largest seasonal hypoxic water basins, has been reported to be expanding rapidly in recent decades. However, the microbial community dynamics and responses to this water hypoxia are still unclear. In this study, we examined the abundance, community composition, and distribution of sedimentary archaea, one important component of microbial communities in the Changjiang River Estuary and the East China Sea (ECS). Our results indicated that Thaumarchaeota and Bathyarchaeota were predominant archaeal groups in these research areas, with their 16S rRNA gene abundance ranged from 8.55 × 106 to 7.51 × 108 and 3.18 × 105 to 1.11 × 108 copies/g, respectively. The sedimentary archaeal community was mainly influenced by DO, together with the concentration of ammonium, nitrate, and sulfide. In addition, distinct differences in the archaeal community's composition, abundance, and driving factors were discovered between samples from hypoxia and non-hypoxia stations. Furtherly, microbial networks suggest various microbes leading the different activities in hypoxic and normoxic environments. Bathyarchaeota and Thermoprofundales were "key stone" archaeal members of the low-DO network, whereas Thaumarchaeota constituted a significant component of the high-DO network. Our results provide a clear picture of the sedimentary archaeal community in coastal hypoxia zones and indicates potential distinctions of archaea in hypoxia and non-hypoxia environments, including ecological niches and metabolic functions. IMPORTANCE In this study, the sedimentary archaeal community composition and abundance were detailed revealed and quantified based on 16S rRNA genes off the Changjiang River Estuary. We found that the community composition was distinct between hypoxia and non-hypoxia regions, while Thaumarchaeota and Bathyarchaeota dominated in non-hypoxia and hypoxia samples, respectively. In hypoxia regions, the sedimentary archaea were mainly affected by salinity, ammonium, and nitrate, whereas total organic carbon, total nitrogen, and sulfide were major influencing factors in non-hypoxia regions. The distinct microbial network may suggest the niche difference of archaeal community under various oxygen level.
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Affiliation(s)
- Dayu Zou
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, Shenzhen, China
- Key Laboratory of Optoelectronic Devices and Systems, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, Guangdong, China
| | - Hongliang Li
- Key Laboratory of Marine Ecosystem Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
| | - Ping Du
- Key Laboratory of Marine Ecosystem Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China
| | - Bin Wang
- Key Laboratory of Marine Ecosystem Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China
| | - Hua Lin
- Key Laboratory of Marine Ecosystem Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China
| | - Hongbin Liu
- Department of Ocean Science and Hong Kong Branch of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), The Hong Kong University of Science and Technology, Hong Kong SAR, China
| | - Jianfang Chen
- Key Laboratory of Marine Ecosystem Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, 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, Guangdong, China
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20
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The Polar Fox Lagoon in Siberia harbours a community of Bathyarchaeota possessing the potential for peptide fermentation and acetogenesis. Antonie Van Leeuwenhoek 2022; 115:1229-1244. [PMID: 35947314 PMCID: PMC9534799 DOI: 10.1007/s10482-022-01767-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 07/18/2022] [Indexed: 11/05/2022]
Abstract
Archaea belonging to the phylum Bathyarchaeota are the predominant archaeal species in cold, anoxic marine sediments and additionally occur in a variety of habitats, both natural and man-made. Metagenomic and single-cell sequencing studies suggest that Bathyarchaeota may have a significant impact on the emissions of greenhouse gases into the atmosphere, either through direct production of methane or through the degradation of complex organic matter that can subsequently be converted into methane. This is especially relevant in permafrost regions where climate change leads to thawing of permafrost, making high amounts of stored carbon bioavailable. Here we present the analysis of nineteen draft genomes recovered from a sediment core metagenome of the Polar Fox Lagoon, a thermokarst lake located on the Bykovsky Peninsula in Siberia, Russia, which is connected to the brackish Tiksi Bay. We show that the Bathyarchaeota in this lake are predominantly peptide degraders, producing reduced ferredoxin from the fermentation of peptides, while degradation pathways for plant-derived polymers were found to be incomplete. Several genomes encoded the potential for acetogenesis through the Wood-Ljungdahl pathway, but methanogenesis was determined to be unlikely due to the lack of genes encoding the key enzyme in methanogenesis, methyl-CoM reductase. Many genomes lacked a clear pathway for recycling reduced ferredoxin. Hydrogen metabolism was also hardly found: one type 4e [NiFe] hydrogenase was annotated in a single MAG and no [FeFe] hydrogenases were detected. Little evidence was found for syntrophy through formate or direct interspecies electron transfer, leaving a significant gap in our understanding of the metabolism of these organisms.
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21
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Prasitwuttisak W, Hoshiko Y, Maeda T, Haraguchi A, Yanagawa K. Microbial Community Structures and Methanogenic Functions in Wetland Peat Soils. Microbes Environ 2022; 37. [PMID: 35851269 PMCID: PMC9530717 DOI: 10.1264/jsme2.me22004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Methane metabolism in wetlands involves diverse groups of bacteria and archaea, which are responsible for the biological decomposition of organic matter under certain anoxic conditions. Recent advances in environmental omics revealed the phylogenetic diversity of novel microbial lineages, which have not been previously placed in the traditional tree of life. The present study aimed to verify the key players in methane production, either well-known archaeal members or recently identified lineages, in peat soils collected from wetland areas in Japan. Based on an analysis of microbial communities using 16S rRNA gene sequencing and the molecular cloning of the functional gene, mcrA, a marker gene for methanogenesis, methanogenic archaea belonging to Methanomicrobiales, Methanosarcinales, Methanobacteriales, and Methanomassiliicoccales were detected in anoxic peat soils, suggesting the potential of CH4 production in this natural wetland. “Candidatus Bathyarchaeia”, archaea with vast metabolic capabilities that is widespread in anoxic environments, was abundant in subsurface peat soils (up to 96% of the archaeal community) based on microbial gene quantification by qPCR. These results emphasize the importance of discovering archaea members outside of traditional methanogenic lineages that may have significant functions in the wetland biogeochemical cycle.
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Affiliation(s)
| | - Yuki Hoshiko
- Department of Biological Functions Engineering, Graduate School of Life Sciences and Systems Engineering, Kyushu Institute of Technology
| | - Toshinari Maeda
- Department of Biological Functions Engineering, Graduate School of Life Sciences and Systems Engineering, Kyushu Institute of Technology
| | - Akira Haraguchi
- Faculty of Environmental Engineering, The University of Kitakyushu
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22
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Méheust R, Castelle CJ, Jaffe AL, Banfield JF. Conserved and lineage-specific hypothetical proteins may have played a central role in the rise and diversification of major archaeal groups. BMC Biol 2022; 20:154. [PMID: 35790962 PMCID: PMC9258230 DOI: 10.1186/s12915-022-01348-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Accepted: 06/09/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Archaea play fundamental roles in the environment, for example by methane production and consumption, ammonia oxidation, protein degradation, carbon compound turnover, and sulfur compound transformations. Recent genomic analyses have profoundly reshaped our understanding of the distribution and functionalities of Archaea and their roles in eukaryotic evolution. RESULTS Here, 1179 representative genomes were selected from 3197 archaeal genomes. The representative genomes clustered based on the content of 10,866 newly defined archaeal protein families (that will serve as a community resource) recapitulates archaeal phylogeny. We identified the co-occurring proteins that distinguish the major lineages. Those with metabolic roles were consistent with experimental data. However, two families specific to Asgard were determined to be new eukaryotic signature proteins. Overall, the blocks of lineage-specific families are dominated by proteins that lack functional predictions. CONCLUSIONS Given that these hypothetical proteins are near ubiquitous within major archaeal groups, we propose that they were important in the origin of most of the major archaeal lineages. Interestingly, although there were clearly phylum-specific co-occurring proteins, no such blocks of protein families were shared across superphyla, suggesting a burst-like origin of new lineages early in archaeal evolution.
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Affiliation(s)
- Raphaël Méheust
- Department of Earth and Planetary Science, University of California, Berkeley, CA, USA. .,Innovative Genomics Institute, University of California, Berkeley, CA, USA. .,LABGeM, Génomique Métabolique, Genoscope, Institut François Jacob, CEA, Evry, France.
| | - Cindy J Castelle
- Department of Earth and Planetary Science, University of California, Berkeley, CA, USA.,Chan Zuckerberg Biohub, San Francisco, CA, USA
| | - Alexander L Jaffe
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA
| | - Jillian F Banfield
- Department of Earth and Planetary Science, University of California, Berkeley, CA, USA. .,Innovative Genomics Institute, University of California, Berkeley, CA, USA. .,Chan Zuckerberg Biohub, San Francisco, CA, USA. .,Department of Environmental Science, Policy, and Management, University of California, Berkeley, CA, USA.
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23
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Zhu QZ, Wegener G, Hinrichs KU, Elvert M. Activity of Ancillary Heterotrophic Community Members in Anaerobic Methane-Oxidizing Cultures. Front Microbiol 2022; 13:912299. [PMID: 35722308 PMCID: PMC9201399 DOI: 10.3389/fmicb.2022.912299] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Accepted: 05/02/2022] [Indexed: 11/13/2022] Open
Abstract
Consortia of anaerobic methanotrophic archaea (ANME) and sulfate-reducing bacteria mediate the anaerobic oxidation of methane (AOM) in marine sediments. However, even sediment-free cultures contain a substantial number of additional microorganisms not directly related to AOM. To track the heterotrophic activity of these community members and their possible relationship with AOM, we amended meso- (37°C) and thermophilic (50°C) AOM cultures (dominated by ANME-1 archaea and their partner bacteria of the Seep-SRB2 clade or Candidatus Desulfofervidus auxilii) with L-leucine-3-13C (13C-leu). Various microbial lipids incorporated the labeled carbon from this amino acid, independent of the presence of methane as an energy source, specifically bacterial fatty acids, such as iso and anteiso-branched C15:0 and C17:0, as well as unsaturated C18:1ω9 and C18:1ω7. In natural methane-rich environments, these bacterial fatty acids are strongly 13C-depleted. We, therefore, suggest that those fatty acids are produced by ancillary bacteria that grow on 13C-depleted necromass or cell exudates/lysates of the AOM core communities. Candidates that likely benefit from AOM biomass are heterotrophic bacterial members of the Spirochetes and Anaerolineae—known to produce abundant branched fatty acids and present in all the AOM enrichment cultures. For archaeal lipids, we observed minor 13C-incorporation, but still suggesting some 13C-leu anabolism. Based on their relatively high abundance in the culture, the most probable archaeal candidates are Bathyarchaeota, Thermoplasmatales, and Lokiarchaeota. The identified heterotrophic bacterial and archaeal ancillary members are likely key players in organic carbon recycling in anoxic marine sediments.
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Affiliation(s)
- Qing-Zeng Zhu
- MARUM - Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | - Gunter Wegener
- MARUM - Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany.,Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Kai-Uwe Hinrichs
- MARUM - Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany.,Faculty of Geosciences, University of Bremen, Bremen, Germany
| | - Marcus Elvert
- MARUM - Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany.,Faculty of Geosciences, University of Bremen, Bremen, Germany
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24
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Cai M, Duan C, Zhang X, Pan J, Liu Y, Zhang C, Li M. Genomic and transcriptomic dissection of Theionarchaea in marine ecosystem. SCIENCE CHINA. LIFE SCIENCES 2022; 65:1222-1234. [PMID: 34668130 DOI: 10.1007/s11427-021-1996-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Accepted: 08/17/2021] [Indexed: 11/24/2022]
Abstract
Theionarchaea is a recently described archaeal class within the Euryarchaeota. While it is widely distributed in sediment ecosystems, little is known about its metabolic potential and ecological features. Here, we used metagenomics and metatranscriptomics to characterize 12 theionarchaeal metagenome-assembled genomes, which were further divided into two subgroups, from coastal mangrove sediments of China and seawater columns of the Yap Trench. Genomic analysis revealed that apart from the canonical sulfhydrogenase, Theionarchaea harbor genes encoding heliorhodopsin, group 4 [NiFe]-hydrogenase, and flagellin, in which genes for heliorhodopsin and group 4 [NiFe]-hydrogenase were transcribed in mangrove sediment. Further, the theionarchaeal substrate spectrum may be broader than previously reported as revealed by metagenomics and metatranscriptomics, and the potential carbon substrates include detrital proteins, hemicellulose, ethanol, and CO2. The genes for organic substrate metabolism (mainly detrital protein and amino acid metabolism genes) have relatively higher transcripts in the top sediment layers in mangrove wetlands. In addition, co-occurrence analysis suggested that the degradation of these organic compounds by Theionarchaea might be processed in syntrophy with fermenters (e.g., Chloroflexi) and methanogens. Collectively, these observations expand the current knowledge of the metabolic potential of Theionarchaea, and shed light on the metabolic strategies and roles of these archaea in the marine ecosystems.
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Affiliation(s)
- Mingwei Cai
- Archaeal Biology Center, Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, 518060, China
| | - Changhai Duan
- Archaeal Biology Center, Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, 518060, China
- SZU-HKUST Joint PhD Program in Marine Environmental Science, Shenzhen University, Shenzhen, 518060, China
| | - Xinxu Zhang
- Archaeal Biology Center, Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, 518060, China
| | - Jie Pan
- Archaeal Biology Center, Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, 518060, China
| | - Yang Liu
- Archaeal Biology Center, Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, 518060, China
| | - Cuijing Zhang
- Archaeal Biology Center, Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, 518060, China
| | - Meng Li
- Archaeal Biology Center, Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, 518060, China.
- SZU-HKUST Joint PhD Program in Marine Environmental Science, Shenzhen University, Shenzhen, 518060, China.
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25
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Diverse methylotrophic methanogenic archaea cause high methane emissions from seagrass meadows. Proc Natl Acad Sci U S A 2022; 119:2106628119. [PMID: 35165204 PMCID: PMC8892325 DOI: 10.1073/pnas.2106628119] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/23/2021] [Indexed: 11/18/2022] Open
Abstract
Marine coastlines colonized by seagrasses are a net source of methane to the atmosphere. However, methane emissions from these environments are still poorly constrained, and the underlying processes and responsible microorganisms remain largely unknown. Here, we investigated methane turnover in seagrass meadows of Posidonia oceanica in the Mediterranean Sea. The underlying sediments exhibited median net fluxes of methane into the water column of ca. 106 µmol CH4 ⋅ m-2 ⋅ d-1 Our data show that this methane production was sustained by methylated compounds produced by the plant, rather than by fermentation of buried organic carbon. Interestingly, methane production was maintained long after the living plant died off, likely due to the persistence of methylated compounds, such as choline, betaines, and dimethylsulfoniopropionate, in detached plant leaves and rhizomes. We recovered multiple mcrA gene sequences, encoding for methyl-coenzyme M reductase (Mcr), the key methanogenic enzyme, from the seagrass sediments. Most retrieved mcrA gene sequences were affiliated with a clade of divergent Mcr and belonged to the uncultured Candidatus Helarchaeota of the Asgard superphylum, suggesting a possible involvement of these divergent Mcr in methane metabolism. Taken together, our findings identify the mechanisms controlling methane emissions from these important blue carbon ecosystems.
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26
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Torres-Beltrán M, Vargas-Gastélum L, Magdaleno-Moncayo D, Riquelme M, Herguera-García JC, Prieto-Davó A, Lago-Lestón A. The metabolic core of the prokaryotic community from deep-sea sediments of the southern Gulf of Mexico shows different functional signatures between the continental slope and abyssal plain. PeerJ 2021; 9:e12474. [PMID: 34993013 PMCID: PMC8679910 DOI: 10.7717/peerj.12474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 10/20/2021] [Indexed: 11/20/2022] Open
Abstract
Marine sediments harbor an outstanding level of microbial diversity supporting diverse metabolic activities. Sediments in the Gulf of Mexico (GoM) are subjected to anthropic stressors including oil pollution with potential effects on microbial community structure and function that impact biogeochemical cycling. We used metagenomic analyses to provide significant insight into the potential metabolic capacity of the microbial community in Southern GoM deep sediments. We identified genes for hydrocarbon, nitrogen and sulfur metabolism mostly affiliated with Alpha and Betaproteobacteria, Acidobacteria, Chloroflexi and Firmicutes, in relation to the use of alternative carbon and energy sources to thrive under limiting growth conditions, and metabolic strategies to cope with environmental stressors. In addition, results show amino acids metabolism could be associated with sulfur metabolism carried out by Acidobacteria, Chloroflexi and Firmicutes, and may play a crucial role as a central carbon source to favor bacterial growth. We identified the tricarboxylic acid cycle (TCA) and aspartate, glutamate, glyoxylate and leucine degradation pathways, as part of the core carbon metabolism across samples. Further, microbial communities from the continental slope and abyssal plain show differential metabolic capacities to cope with environmental stressors such as oxidative stress and carbon limiting growth conditions, respectively. This research combined taxonomic and functional information of the microbial community from Southern GoM sediments to provide fundamental knowledge that links the prokaryotic structure to its potential function and which can be used as a baseline for future studies to model microbial community responses to environmental perturbations, as well as to develop more accurate mitigation and conservation strategies.
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Affiliation(s)
- Mónica Torres-Beltrán
- Departamento de Innovación Biomédica, Centro de Investigación Científica y de Educación Superior de Ensenada, Ensenada, Baja California, Mexico
| | - Lluvia Vargas-Gastélum
- Departamento de Microbiología, Centro de Investigación Científica y de Educación Superior de Ensenada, Ensenada, Baja California, Mexico
| | - Dante Magdaleno-Moncayo
- Facultad de Ingeniería, Arquitectura y Diseño, Universidad Autónoma de Baja California, Ensenada, Baja California, Mexico
| | - Meritxell Riquelme
- Departamento de Microbiología, Centro de Investigación Científica y de Educación Superior de Ensenada, Ensenada, Baja California, Mexico
| | - Juan Carlos Herguera-García
- Departamento de Ecología Marina, Centro de Investigación Científica y de Educación Superior de Ensenada, Ensenada, Baja California, Mexico
| | - Alejandra Prieto-Davó
- Facultad de Química, Universidad Nacional Autónoma de México, Sisal, Yucatán, Mexico
| | - Asunción Lago-Lestón
- Departamento de Innovación Biomédica, Centro de Investigación Científica y de Educación Superior de Ensenada, Ensenada, Baja California, Mexico
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27
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Chen Y, Qiu K, Zhong Z, Zhou T. Influence of Environmental Factors on the Variability of Archaeal Communities in a Karst Wetland. Front Microbiol 2021; 12:675665. [PMID: 34539596 PMCID: PMC8448418 DOI: 10.3389/fmicb.2021.675665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 07/27/2021] [Indexed: 12/02/2022] Open
Abstract
Archaea are ubiquitous and play an important role in elemental cycles in Earth’s biosphere; but little is known about their diversity, distribution, abundance, and impact in karst environments. The present study investigated the effect of environmental factors on the variability of archaeal communities in the sediment of the Huixian karst wetland, the largest karst wetland in South China. Sediment cores were obtained from four sampling sites with different water depths and macrophyte inhabitants in both the winter of 2016 and the summer of 2018. The community analysis was based on PacBio sequencing and quantitative PCR of the archaeal 16S rRNA gene. The results showed that Euryarchaeota (57.4%) and Bathyarchaeota (38.7%) were dominant in all the samples. Methanogenic Methanosarcinales (25.1%) and Methanomicrobiales (13.7%), and methanotrophic archaea ANME-2d (9.0%) were the dominant Euryarchaeota; MCG-11 (16.5%), MCG-6 (9.1%), and MCG-5b (5.5%) were the dominant Bathyarchaeota. The community composition remained stable between summer and winter, and the vertical distributions of the archaeal phyla conformed to two patterns among the four sampling sites. In the winter samples, the archaeal 16S rRNA gene abundance was approximately 1.0E+10 copies/g of wet sediment and the Shannon index was 7.3±5, which were significantly higher than in the summer samples and in other karst environments. A correlation analysis showed that the moisture content and pH were the factors that mostly affected the archaeal communities. The prevalence of nitrate in the summer may be a key factor causing a significant decrease in archaeal abundance and diversity. Two features specific to karst environments, calcium-richness and weak alkalescence of the water supplies, may benefit the prevalence of bathyarchaeotal subgroups MCG-11, MCG-5b, and MCG-6. These results suggest that in karst wetlands, most of the archaea belong to clades that have significant roles in carbon turnover; their composition remains stable, but their abundance and diversity vary significantly from season to season.
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Affiliation(s)
- Ying Chen
- School of Biotechnology, Guilin Medical University, Guilin, China
| | - Kairui Qiu
- School of Biotechnology, Guilin Medical University, Guilin, China
| | - Ziyuan Zhong
- School of Biotechnology, Guilin Medical University, Guilin, China
| | - Tao Zhou
- School of Biotechnology, Guilin Medical University, Guilin, China
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28
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Tahon G, Patricia Geesink, Ettema TJG. Expanding Archaeal Diversity and Phylogeny: Past, Present, and Future. Annu Rev Microbiol 2021; 75:359-381. [PMID: 34351791 DOI: 10.1146/annurev-micro-040921-050212] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The discovery of the Archaea is a major scientific hallmark of the twentieth century. Since then, important features of their cell biology, physiology, ecology, and diversity have been revealed. Over the course of some 40 years, the diversity of known archaea has expanded from 2 to about 30 phyla comprising over 20,000 species. Most of this archaeal diversity has been revealed by environmental 16S rRNA amplicon sequencing surveys using a broad range of universal and targeted primers. Of the few primers that target a large fraction of known archaeal diversity, all display a bias against recently discovered lineages, which limits studies aiming to survey overall archaeal diversity. Induced by genomic exploration of archaeal diversity, and improved phylogenomics approaches, archaeal taxonomic classification has been frequently revised. Due to computational limitations and continued discovery of new lineages, a stable archaeal phylogeny is not yet within reach. Obtaining phylogenetic and taxonomic consensus of archaea should be a high priority for the archaeal research community. Expected final online publication date for the Annual Review of Microbiology, Volume 75 is October 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Guillaume Tahon
- Laboratory of Microbiology, Wageningen University and Research, 6700 EH Wageningen, The Netherlands; , ,
| | - Patricia Geesink
- Laboratory of Microbiology, Wageningen University and Research, 6700 EH Wageningen, The Netherlands; , ,
| | - Thijs J G Ettema
- Laboratory of Microbiology, Wageningen University and Research, 6700 EH Wageningen, The Netherlands; , ,
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29
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Comparative Genomics Reveals Thermal Adaptation and a High Metabolic Diversity in " Candidatus Bathyarchaeia". mSystems 2021; 6:e0025221. [PMID: 34282939 PMCID: PMC8407382 DOI: 10.1128/msystems.00252-21] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
"Candidatus Bathyarchaeia" is a phylogenetically diverse and widely distributed lineage often in high abundance in anoxic submarine sediments; however, their evolution and ecological roles in terrestrial geothermal habitats are poorly understood. In the present study, 35 Ca. Bathyarchaeia metagenome-assembled genomes (MAGs) were recovered from hot spring sediments in Tibet and Yunnan, China. Phylogenetic analysis revealed all MAGs of Ca. Bathyarchaeia can be classified into 7 orders and 15 families. Among them, 4 families have been first discovered in the present study, significantly expanding the known diversity of Ca. Bathyarchaeia. Comparative genomics demonstrated Ca. Bathyarchaeia MAGs from thermal habitats to encode a large variety of genes related to carbohydrate degradation, which are likely a metabolic adaptation of these organisms to a lifestyle at high temperatures. At least two families are potential methanogens/alkanotrophs, indicating a potential for the catalysis of short-chain hydrocarbons. Three MAGs from Family-7.3 are identified as alkanotrophs due to the detection of an Mcr complex. Family-2 contains the largest number of genes relevant to alkyl-CoM transformation, indicating the potential for methylotrophic methanogenesis, although their evolutionary history suggests the ancestor of Ca. Bathyarchaeia was unable to metabolize alkanes. Subsequent lineages have acquired the ability via horizontal gene transfer. Overall, our study significantly expands our knowledge and understanding of the metabolic capabilities, habitat adaptations, and evolution of Ca. Bathyarchaeia in thermal environments. IMPORTANCE Ca. Bathyarchaeia MAGs from terrestrial hot spring habitats are poorly revealed, though they have been studied extensively in marine ecosystems. In this study, we uncovered the metabolic capabilities and ecological role of Ca. Bathyarchaeia in hot springs and give a comprehensive comparative analysis between thermal and nonthermal habitats to reveal the thermal adaptability of Ca. Bathyarchaeia. Also, we attempt to determine the evolutionary history of methane/alkane metabolism in Ca. Bathyarchaeia, since it appears to be the first archaea beyond Euryarchaeota which contains the mcrABG genes. The reclassification of Ca. Bathyarchaeia and significant genomic differences among different lineages largely expand our knowledge on these cosmopolitan archaea, which will be beneficial in guiding the future studies.
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30
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Zhang CJ, Chen YL, Sun YH, Pan J, Cai MW, Li M. Diversity, metabolism and cultivation of archaea in mangrove ecosystems. MARINE LIFE SCIENCE & TECHNOLOGY 2021; 3:252-262. [PMID: 37073347 PMCID: PMC10077227 DOI: 10.1007/s42995-020-00081-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 10/19/2020] [Indexed: 05/03/2023]
Abstract
Mangroves comprise a globally significant intertidal ecosystem that contains a high diversity of microorganisms, including fungi, bacteria and archaea. Archaea is a major domain of life that plays important roles in biogeochemical cycles in these ecosystems. In this review, the potential roles of archaea in mangroves are briefly highlighted. Then, the diversity and metabolism of archaeal community of mangrove ecosystems across the world are summarized and Bathyarchaeota, Euryarchaeota, Thaumarchaeota, Woesearchaeota, and Lokiarchaeota are confirmed as the most abundant and ubiquitous archaeal groups. The metabolic potential of these archaeal groups indicates their important ecological function in carbon, nitrogen and sulfur cycling. Finally, some cultivation strategies that could be applied to uncultivated archaeal lineages from mangrove wetlands are suggested, including refinements to traditional cultivation methods based on genomic and transcriptomic information, and numerous innovative cultivation techniques such as single-cell isolation and high-throughput culturing (HTC). These cultivation strategies provide more opportunities to obtain previously uncultured archaea.
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Affiliation(s)
- Cui-Jing Zhang
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, 518060 China
| | - Yu-Lian Chen
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, 518060 China
| | - Yi-Hua Sun
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, 518060 China
| | - Jie Pan
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, 518060 China
| | - Ming-Wei Cai
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, 518060 China
| | - Meng Li
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, 518060 China
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31
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Hu H, Natarajan VP, Wang F. Towards enriching and isolation of uncultivated archaea from marine sediments using a refined combination of conventional microbial cultivation methods. MARINE LIFE SCIENCE & TECHNOLOGY 2021; 3:231-242. [PMID: 37073339 PMCID: PMC10077295 DOI: 10.1007/s42995-021-00092-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 01/12/2021] [Indexed: 05/03/2023]
Abstract
The archaea that can be readily cultivated in the laboratory are only a small fraction of the total diversity that exists in nature. Although molecular ecology methods, such as metagenomic sequencing, can provide valuable information independent of cell cultivation, it is only through cultivation-based experiments that they may be fully characterized, both for their physiological and ecological properties. Here, we report our efforts towards enriching and isolation of uncultivated archaea from marine sediments using a refined combination of conventional microbial cultivation methods. Initially, cells were retrieved from the sediment samples through a cell extraction procedure and the sediment-free mixed cells were then divided into different size-range fractions by successive filtration through 0.8 µm, 0.6 µm and 0.2 µm membranes. Archaeal 16S rRNA gene analyses indicated noticeable retention of different archaeal groups in different fractions. For each fraction, supplementation with a variety of defined substrates (e.g., methane, sulfate, and lignin) and stepwise dilutions led to highly active enrichment cultures of several archaeal groups with Bathyarchaeota most prominently enriched. Finally, using a roll-bottle technique, three co-cultures consisting of Bathyarchaeota (subgroup-8) and a bacterial species affiliated with either Pseudomonas or Glutamicibacter were obtained. Our results demonstrate that a combination of cell extraction, size fractionation, and roll-bottle isolation methods could be a useful protocol for the successful enrichment and isolation of numerous slow-growing archaeal groups from marine sediments. Supplementary Information The online version contains supplementary material available at 10.1007/s42995-021-00092-0.
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Affiliation(s)
- Haining Hu
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240 China
| | - Vengadesh Perumal Natarajan
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240 China
- School of Oceanography, Shanghai Jiao Tong University, Shanghai, 200240 China
| | - Fengping Wang
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240 China
- School of Oceanography, Shanghai Jiao Tong University, Shanghai, 200240 China
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32
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Kevorkian RT, Callahan S, Winstead R, Lloyd KG. ANME-1 archaea may drive methane accumulation and removal in estuarine sediments. ENVIRONMENTAL MICROBIOLOGY REPORTS 2021; 13:185-194. [PMID: 33462984 DOI: 10.1111/1758-2229.12926] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 12/31/2020] [Accepted: 01/04/2021] [Indexed: 06/12/2023]
Abstract
ANME-1 archaea subsist on the very low energy of anaerobic oxidation of methane (AOM). Most marine sediments shift from net AOM in the sulfate methane transition zone (SMTZ) to methanogenesis in the methane zone (MZ) below it. In White Oak River estuarine sediments, ANME-1 comprised 99.5% of 16S rRNA genes from amplicons and 100% of 16S rRNA genes from metagenomes of the Methanomicrobia in the SMTZ and 99.9% and 98.3%, respectively, in the MZ. Each of the 16 ANME-1 OTUs (97% similarity) had peaks in the SMTZ that coincided with peaks of putative sulfate-reducing bacteria Desulfatiglans sp. and SEEP-SRB1. In the MZ, ANME-1, but none of the putative sulfate-reducing bacteria or cultured methanogens, increased with depth. Our meta-analysis of public data showed only ANME-1 expressed methanogenic genes during both net AOM and net methanogenesis in an enrichment culture. We conclude that ANME-1 perform AOM in the SMTZ and methanogenesis in the MZ of White Oak River sediments. This metabolic flexibility may expand habitable zones in extraterrestrial environments, since it enables greater energy yields in a fluctuating energetic landscape.
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Affiliation(s)
| | - Sean Callahan
- Department of Microbiology, University of Tennessee, Knoxville, TN, USA
| | - Rachel Winstead
- Department of Microbiology, University of Tennessee, Knoxville, TN, USA
| | - Karen G Lloyd
- Department of Microbiology, University of Tennessee, Knoxville, TN, USA
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33
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Pelikan C, Wasmund K, Glombitza C, Hausmann B, Herbold CW, Flieder M, Loy A. Anaerobic bacterial degradation of protein and lipid macromolecules in subarctic marine sediment. THE ISME JOURNAL 2021; 15:833-847. [PMID: 33208892 PMCID: PMC8027456 DOI: 10.1038/s41396-020-00817-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Revised: 10/13/2020] [Accepted: 10/19/2020] [Indexed: 01/30/2023]
Abstract
Microorganisms in marine sediments play major roles in marine biogeochemical cycles by mineralizing substantial quantities of organic matter from decaying cells. Proteins and lipids are abundant components of necromass, yet the taxonomic identities of microorganisms that actively degrade them remain poorly resolved. Here, we revealed identities, trophic interactions, and genomic features of bacteria that degraded 13C-labeled proteins and lipids in cold anoxic microcosms containing sulfidic subarctic marine sediment. Supplemented proteins and lipids were rapidly fermented to various volatile fatty acids within 5 days. DNA-stable isotope probing (SIP) suggested Psychrilyobacter atlanticus was an important primary degrader of proteins, and Psychromonas members were important primary degraders of both proteins and lipids. Closely related Psychromonas populations, as represented by distinct 16S rRNA gene variants, differentially utilized either proteins or lipids. DNA-SIP also showed 13C-labeling of various Deltaproteobacteria within 10 days, indicating trophic transfer of carbon to putative sulfate-reducers. Metagenome-assembled genomes revealed the primary hydrolyzers encoded secreted peptidases or lipases, and enzymes for catabolism of protein or lipid degradation products. Psychromonas species are prevalent in diverse marine sediments, suggesting they are important players in organic carbon processing in situ. Together, this study provides new insights into the identities, functions, and genomes of bacteria that actively degrade abundant necromass macromolecules in the seafloor.
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Affiliation(s)
- Claus Pelikan
- Division of Microbial Ecology, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
- Austrian Polar Research Institute, Vienna, Austria
| | - Kenneth Wasmund
- Division of Microbial Ecology, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria.
- Austrian Polar Research Institute, Vienna, Austria.
| | - Clemens Glombitza
- Department of Biology, Center for Geomicrobiology, Aarhus University, Aarhus, Denmark
- Department of Environmental Systems Science, ETH Zürich, Zürich, Switzerland
| | - Bela Hausmann
- Division of Microbial Ecology, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
- 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
| | - Mathias Flieder
- 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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34
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Loh HQ, Hervé V, Brune A. Metabolic Potential for Reductive Acetogenesis and a Novel Energy-Converting [NiFe] Hydrogenase in Bathyarchaeia From Termite Guts - A Genome-Centric Analysis. Front Microbiol 2021; 11:635786. [PMID: 33613473 PMCID: PMC7886697 DOI: 10.3389/fmicb.2020.635786] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 12/31/2020] [Indexed: 12/11/2022] Open
Abstract
Symbiotic digestion of lignocellulose in the hindgut of higher termites is mediated by a diverse assemblage of bacteria and archaea. During a large-scale metagenomic study, we reconstructed 15 metagenome-assembled genomes of Bathyarchaeia that represent two distinct lineages in subgroup 6 (formerly MCG-6) unique to termite guts. One lineage (TB2; Candidatus Termitimicrobium) encodes all enzymes required for reductive acetogenesis from CO2 via an archaeal variant of the Wood–Ljungdahl pathway, involving tetrahydromethanopterin as C1 carrier and an (ADP-forming) acetyl-CoA synthase. This includes a novel 11-subunit hydrogenase, which possesses the genomic architecture of the respiratory Fpo-complex of other archaea but whose catalytic subunit is phylogenetically related to and shares the conserved [NiFe] cofactor-binding motif with [NiFe] hydrogenases of subgroup 4 g. We propose that this novel Fpo-like hydrogenase provides part of the reduced ferredoxin required for CO2 reduction and is driven by the electrochemical membrane potential generated from the ATP conserved by substrate-level phosphorylation; the other part may require the oxidation of organic electron donors, which would make members of TB2 mixotrophic acetogens. Members of the other lineage (TB1; Candidatus Termiticorpusculum) are definitely organotrophic because they consistently lack hydrogenases and/or methylene-tetrahydromethanopterin reductase, a key enzyme of the archaeal Wood–Ljungdahl pathway. Both lineages have the genomic capacity to reduce ferredoxin by oxidizing amino acids and might conduct methylotrophic acetogenesis using unidentified methylated compound(s). Our results indicate that Bathyarchaeia of subgroup 6 contribute to acetate formation in the guts of higher termites and substantiate the genomic evidence for reductive acetogenesis from organic substrates, possibly including methylated compounds, in other uncultured representatives of the phylum.
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Affiliation(s)
- Hui Qi Loh
- Research Group Insect Microbiology and Symbiosis, Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
| | - Vincent Hervé
- Research Group Insect Microbiology and Symbiosis, Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
| | - Andreas Brune
- Research Group Insect Microbiology and Symbiosis, Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
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35
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Liu X, Wang Y, Gu JD. Ecological distribution and potential roles of Woesearchaeota in anaerobic biogeochemical cycling unveiled by genomic analysis. Comput Struct Biotechnol J 2021; 19:794-800. [PMID: 33552450 PMCID: PMC7844129 DOI: 10.1016/j.csbj.2021.01.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 01/06/2021] [Accepted: 01/08/2021] [Indexed: 12/21/2022] Open
Abstract
Woesearchaeota as a newly established member of the superphylum DPANN (Diapherotrites, Parvarchaeota, Aenigmarchaeota, Nanoarchaeota and Nanohaloarchaea) are surprisingly abundant and diverse in a wide variety of environments, including deep oil reservoir, sulfuric springs and anoxic aquifers, indicating a high diversity of their roles in global biogeochemical cycles. However, ecological functions of them remain elusive. To fill up this gap, we analyzed and compared the global distribution patterns of Woesearchaeota using the genomes available publicly. As a result, both ecological distribution patterns and metabolic predictions support a key role of woesearchaeotal lineages in cycling of carbon, nitrogen, and sulfur. Multivariate regression analysis reveals that Woesearchaeota might function in consortium with methanogens in the cycling of carbon in anaerobic environments, particularly in soils or sediments. Moreover, comparative genomic analysis and ecological distribution suggest the potential roles of Woesearchaeota in the processes of denitrification, nitrogen fixation, and dissimilatory nitrite reduction, especially in the wastewater treatment systems; and also uncovered the potential capability of sulfate reduction, sulfide oxidation and thiosulfate oxidation in sulfuric or sulfidic-rich environments. Our findings add more information into the ecological roles of archaea in the anoxic environment.
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Affiliation(s)
- Xiaobo Liu
- Environmental Engineering Program, Guangdong Technion-Israel Institute of Technology (GTIIT), 241 Daxue Road, Shantou 515063, Guangdong, China
| | - Yali Wang
- Conservation Center, Guangdong Museum, 2 Zhujiang East Road, Tianhe District, Guangzhou 510623, Guangdong, China
| | - Ji-Dong Gu
- Environmental Engineering Program, Guangdong Technion-Israel Institute of Technology (GTIIT), 241 Daxue Road, Shantou 515063, Guangdong, China
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36
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Abstract
Microbes in marine sediments represent a large portion of the biosphere, and resolving their ecology is crucial for understanding global ocean processes. Single-gene diversity surveys have revealed several uncultured lineages that are widespread in ocean sediments and whose ecological roles are unknown, and advancements in the computational analysis of increasingly large genomic data sets have made it possible to reconstruct individual genomes from complex microbial communities. Using these metagenomic approaches to characterize sediments is transforming our view of microbial communities on the ocean floor and the biodiversity of the planet. In recent years, marine sediments have been a prominent source of new lineages in the tree of life. The incorporation of these lineages into existing phylogenies has revealed that many belong to distinct phyla, including archaeal phyla that are advancing our understanding of the origins of cellular complexity and eukaryotes. Detailed comparisons of the metabolic potentials of these new lineages have made it clear that uncultured bacteria and archaea are capable of mediating key previously undescribed steps in carbon and nutrient cycling.
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Affiliation(s)
- Brett J Baker
- Department of Marine Science and Marine Science Institute, University of Texas at Austin, Port Aransas, Texas 78373, USA;
| | - Kathryn E Appler
- Department of Marine Science and Marine Science Institute, University of Texas at Austin, Port Aransas, Texas 78373, USA;
| | - Xianzhe Gong
- Department of Marine Science and Marine Science Institute, University of Texas at Austin, Port Aransas, Texas 78373, USA;
- Institute of Marine Science and Technology, Shandong University, Qingdao, Shandong 266237, China;
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37
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Lai D, Hedlund BP, Xie W, Liu J, Phelps TJ, Zhang C, Wang P. Impact of Terrestrial Input on Deep-Sea Benthic Archaeal Community Structure in South China Sea Sediments. Front Microbiol 2020; 11:572017. [PMID: 33224115 PMCID: PMC7674655 DOI: 10.3389/fmicb.2020.572017] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 10/15/2020] [Indexed: 12/12/2022] Open
Abstract
Archaea are widespread in marine sediments and play important roles in the cycling of sedimentary organic carbon. However, factors controlling the distribution of archaea in marine sediments are not well understood. Here we investigated benthic archaeal communities over glacial-interglacial cycles in the northern South China Sea and evaluated their responses to sediment organic matter sources and inter-species interactions. Archaea in sediments deposited during the interglacial period Marine Isotope Stage (MIS) 1 (Holocene) were significantly different from those in sediments deposited in MIS 2 and MIS 3 of the Last Glacial Period when terrestrial input to the South China Sea was enhanced based on analysis of the long-chain n-alkane C31. The absolute archaeal 16S rRNA gene abundance in subsurface sediments was highest in MIS 2, coincident with high sedimentation rates and high concentrations of total organic carbon. Soil Crenarchaeotic Group (SCG; Nitrososphaerales) species, the most abundant ammonia-oxidizing archaea in soils, increased dramatically during MIS 2, likely reflecting transport of terrestrial archaea during glacial periods with high sedimentation rates. Co-occurrence network analyses indicated significant association of SCG archaea with benthic deep-sea microbes such as Bathyarchaeota and Thermoprofundales in MIS 2 and MIS 3, suggesting potential interactions among these archaeal groups. Meanwhile, Thermoprofundales abundance was positively correlated with total organic carbon (TOC), along with n-alkane C31 and sedimentation rate, indicating that Thermoprofundales may be particularly important in processing of organic carbon in deep-sea sediments. Collectively, these results demonstrate that the composition of heterotrophic benthic archaea in the South China Sea may be influenced by terrestrial organic input in tune with glacial-interglacial cycles, suggesting a plausible link between global climate change and microbial population dynamics in deep-sea marine sediments.
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Affiliation(s)
- Dengxun Lai
- State Key Laboratory of Marine Geology, Tongji University, Shanghai, China.,School of Life Sciences, University of Nevada, Las Vegas, NV, United States
| | - Brian P Hedlund
- School of Life Sciences, University of Nevada, Las Vegas, NV, United States.,Nevada Institute of Personalized Medicine, University of Nevada, Las Vegas, NV, United States
| | - Wei Xie
- School of Marine Sciences, Sun Yat-sen University, Zhuhai, China.,Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
| | - Jingjing Liu
- State Key Laboratory of Marine Geology, Tongji University, Shanghai, China
| | - Tommy J Phelps
- Earth and Planetary Sciences, University of Tennessee, Knoxville, Knoxville, TN, United States
| | - Chuanlun Zhang
- Shenzhen Key Laboratory of Marine Archaea Geo-Omics, Southern University of Science and Technology, Shenzhen, China.,Department of Ocean Science and Engineering, Southern University of Science and Technology, Shenzhen, China.,Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China.,Shanghai Sheshan National Geophysical Observatory, Shanghai, China
| | - Peng Wang
- State Key Laboratory of Marine Geology, Tongji University, Shanghai, China
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38
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L. Bräuer S, Basiliko N, M. P. Siljanen H, H. Zinder S. Methanogenic archaea in peatlands. FEMS Microbiol Lett 2020; 367:5928548. [DOI: 10.1093/femsle/fnaa172] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 10/16/2020] [Indexed: 12/22/2022] Open
Abstract
ABSTRACT
Methane emission feedbacks in wetlands are predicted to influence global climate under climate change and other anthropogenic stressors. Herein, we review the taxonomy and physiological ecology of the microorganisms responsible for methane production in peatlands. Common in peat soils are five of the eight described orders of methanogens spanning three phyla (Euryarchaeota, Halobacterota and Thermoplasmatota). The phylogenetic affiliation of sequences found in peat suggest that members of the thus-far-uncultivated group Candidatus Bathyarchaeota (representing a fourth phylum) may be involved in methane cycling, either anaerobic oxidation of methane and/or methanogenesis, as at least a few organisms within this group contain the essential gene, mcrA, according to metagenomic data. Methanogens in peatlands are notoriously challenging to enrich and isolate; thus, much remains unknown about their physiology and how methanogen communities will respond to environmental changes. Consistent patterns of changes in methanogen communities have been reported across studies in permafrost peatland thaw where the resulting degraded feature is thermokarst. However much remains to be understood regarding methanogen community feedbacks to altered hydrology and warming in other contexts, enhanced atmospheric pollution (N, S and metals) loading and direct anthropogenic disturbances to peatlands like drainage, horticultural peat extraction, forestry and agriculture, as well as post-disturbance reclamation.
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Affiliation(s)
- Suzanna L. Bräuer
- Appalachian State University, Department of Biology, ASU Box 32027, 572 Rivers Street, Boone, NC 28608-2027 USA
| | - Nathan Basiliko
- Laurentian University, Department of Biology and the Vale Living with Lakes Centre, 935 Ramsey Lake Road, Sudbury, ON P3E 2C6, Canada
| | - Henri M. P. Siljanen
- Eastern Finland University, Department of Environmental and Biological Sciences, Biogeochemistry Research Group, Snellmania Room 4042, Yliopistonranta 1, Kuopio, 70210, Finland
| | - Stephen H. Zinder
- Cornell University, Department of Microbiology, 272 Wing Hall, Ithaca, NY 14850, USA
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39
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Ancestral Reconstructions Decipher Major Adaptations of Ammonia-Oxidizing Archaea upon Radiation into Moderate Terrestrial and Marine Environments. mBio 2020; 11:mBio.02371-20. [PMID: 33051370 PMCID: PMC7554672 DOI: 10.1128/mbio.02371-20] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Unlike all other archaeal lineages, ammonia-oxidizing archaea (AOA) of the phylum Thaumarchaeota are widespread and abundant in all moderate and oxic environments on Earth. The evolutionary adaptations that led to such unprecedented ecological success of a microbial clade characterized by highly conserved energy and carbon metabolisms have, however, remained underexplored. Here, we reconstructed the genomic content and growth temperature of the ancestor of all AOA, as well as the ancestors of the marine and soil lineages, based on 39 available complete or nearly complete genomes of AOA. Our evolutionary scenario depicts an extremely thermophilic, autotrophic, aerobic ancestor from which three independent lineages of a marine and two terrestrial groups radiated into moderate environments. Their emergence was paralleled by (i) a continuous acquisition of an extensive collection of stress tolerance genes mostly involved in redox maintenance and oxygen detoxification, (ii) an expansion of regulatory capacities in transcription and central metabolic functions, and (iii) an extended repertoire of cell appendages and modifications related to adherence and interactions with the environment. Our analysis provides insights into the evolutionary transitions and key processes that enabled the conquest of the diverse environments in which contemporary AOA are found.
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40
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Ramírez GA, McKay LJ, Fields MW, Buckley A, Mortera C, Hensen C, Ravelo AC, Teske AP. The Guaymas Basin Subseafloor Sedimentary Archaeome Reflects Complex Environmental Histories. iScience 2020; 23:101459. [PMID: 32861995 PMCID: PMC7476861 DOI: 10.1016/j.isci.2020.101459] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 07/31/2020] [Accepted: 08/11/2020] [Indexed: 01/13/2023] Open
Abstract
We explore archaeal distributions in sedimentary subseafloor habitats of Guaymas Basin and the adjacent Sonora Margin, located in the Gulf of California, México. Sampling locations include (1) control sediments without hydrothermal or seep influence, (2) Sonora Margin sediments underlying oxygen minimum zone water, (3) compacted, highly reduced sediments from a pressure ridge with numerous seeps at the base of the Sonora Margin, and (4) sediments impacted by hydrothermal circulation at the off-axis Ringvent site. Generally, archaeal communities largely comprise Bathyarchaeal lineages, members of the Hadesarchaea, MBG-D, TMEG, and ANME-1 groups. Variations in archaeal community composition reflect locally specific environmental challenges. Background sediments are divided into surface and subsurface niches. Overall, the environmental setting and history of a particular site, not isolated biogeochemical properties out of context, control the subseafloor archaeal communities in Guaymas Basin and Sonora Margin sediments.
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Affiliation(s)
- Gustavo A. Ramírez
- Department of Marine Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
- College of Veterinary Medicine, Western University of Health Sciences, Pomona, CA, USA
| | - Luke J. McKay
- Department of Land Resources and Environmental Sciences, Montana State University, Bozeman, MT, USA
- Center for Biofilm Engineering, Montana State University, Bozeman, MT, USA
| | - Matthew W. Fields
- Center for Biofilm Engineering, Montana State University, Bozeman, MT, USA
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, USA
| | - Andrew Buckley
- Department of Marine Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Carlos Mortera
- Instituto de Geofisica, Universidad Nacional Autónoma de México, Coyoacán, México
| | | | - Ana Christina Ravelo
- Ocean Sciences Department, University of California at Santa Cruz, Santa Cruz, CA, USA
| | - Andreas P. Teske
- Department of Marine Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
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41
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Carrier V, Svenning MM, Gründger F, Niemann H, Dessandier PA, Panieri G, Kalenitchenko D. The Impact of Methane on Microbial Communities at Marine Arctic Gas Hydrate Bearing Sediment. Front Microbiol 2020; 11:1932. [PMID: 33071992 PMCID: PMC7541813 DOI: 10.3389/fmicb.2020.01932] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 07/22/2020] [Indexed: 01/26/2023] Open
Abstract
Cold seeps are characterized by high biomass, which is supported by the microbial oxidation of the available methane by capable microorganisms. The carbon is subsequently transferred to higher trophic levels. South of Svalbard, five geological mounds shaped by the formation of methane gas hydrates, have been recently located. Methane gas seeping activity has been observed on four of them, and flares were primarily concentrated at their summits. At three of these mounds, and along a distance gradient from their summit to their outskirt, we investigated the eukaryotic and prokaryotic biodiversity linked to 16S and 18S rDNA. Here we show that local methane seepage and other environmental conditions did affect the microbial community structure and composition. We could not demonstrate a community gradient from the summit to the edge of the mounds. Instead, a similar community structure in any methane-rich sediments could be retrieved at any location on these mounds. The oxidation of methane was largely driven by anaerobic methanotrophic Archaea-1 (ANME-1) and the communities also hosted high relative abundances of sulfate reducing bacterial groups although none demonstrated a clear co-occurrence with the predominance of ANME-1. Additional common taxa were observed and their abundances were likely benefiting from the end products of methane oxidation. Among these were sulfide-oxidizing Campilobacterota, organic matter degraders, such as Bathyarchaeota, Woesearchaeota, or thermoplasmatales marine benthic group D, and heterotrophic ciliates and Cercozoa.
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Affiliation(s)
- Vincent Carrier
- Department of Arctic and Marine Biology, The Arctic University of Norway, Tromsø, Norway.,Centre for Arctic Gas Hydrate, Environment and Climate, The Arctic University of Norway, Tromsø, Norway
| | - Mette M Svenning
- Department of Arctic and Marine Biology, The Arctic University of Norway, Tromsø, Norway.,Centre for Arctic Gas Hydrate, Environment and Climate, The Arctic University of Norway, Tromsø, Norway
| | - Friederike Gründger
- Department of Bioscience, Arctic Research Centre, Aarhus University, Aarhus, Denmark
| | - Helge Niemann
- Centre for Arctic Gas Hydrate, Environment and Climate, The Arctic University of Norway, Tromsø, Norway.,Department of Marine Microbiology and Biogeochemistry, Royal Netherlands Institute for Sea Research, and Utrecht University, Den Burg, Netherlands.,Department of Earth Sciences, Faculty of Geosciences, Utrecht University, Utrecht, Netherlands
| | - Pierre-Antoine Dessandier
- Centre for Arctic Gas Hydrate, Environment and Climate, The Arctic University of Norway, Tromsø, Norway
| | - Giuliana Panieri
- Centre for Arctic Gas Hydrate, Environment and Climate, The Arctic University of Norway, Tromsø, Norway
| | - Dimitri Kalenitchenko
- Centre for Arctic Gas Hydrate, Environment and Climate, The Arctic University of Norway, Tromsø, Norway
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Evidence for a Growth Zone for Deep-Subsurface Microbial Clades in Near-Surface Anoxic Sediments. Appl Environ Microbiol 2020; 86:AEM.00877-20. [PMID: 32709727 DOI: 10.1128/aem.00877-20] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2020] [Accepted: 07/17/2020] [Indexed: 11/20/2022] Open
Abstract
Global marine sediments harbor a large and highly diverse microbial biosphere, but the mechanism by which this biosphere is established during sediment burial is largely unknown. During burial in marine sediments, concentrations of easily metabolized organic compounds and total microbial cell abundance decrease. However, it is unknown whether some microbial clades increase with depth. We show total population increases in 38 microbial families over 3 cm of sediment depth in the upper 7.5 cm of White Oak River (WOR) estuary sediments. Clades that increased with depth were more often associated with one or more of the following: anaerobes, uncultured, or common in deep marine sediments relative to those that decreased. Maximum doubling times (in situ steady-state growth rates could be faster to balance cell decay) were estimated as 2 to 25 years by combining sedimentation rate with either quantitative PCR (qPCR) or the product of the fraction read abundance of 16S rRNA genes and total cell counts (FRAxC). Doubling times were within an order of magnitude of each other in two adjacent cores, as well as in two laboratory enrichments of Cape Lookout Bight (CLB), NC, sediments (average difference of 28% ± 19%). qPCR and FRAxC in sediment cores and laboratory enrichments produced similar doubling times for key deep subsurface uncultured clades Bathyarchaeota (8.7 ± 1.9 years) and Thermoprofundales/MBG-D (4.1 ± 0.7 years). We conclude that common deep subsurface microbial clades experience a narrow zone of growth in shallow sediments, offering an opportunity for selection of long-term subsistence traits after resuspension events.IMPORTANCE Many studies show that the uncultured microbes that dominate global marine sediments do not actually increase in population size as they are buried in marine sediments; rather, they exist in a sort of prolonged torpor for thousands of years. This is because, although studies have shown biomass turnover in these clades, no evidence has ever been found that deeper sediments have larger populations for specific clades than shallower layers. We discovered that they actually do increase population sizes during burial, but only in the upper few centimeters. This suggests that marine sediments may be a vast repository of mostly nongrowing microbes with a thin and relatively rapid area of cell abundance increase in the upper 10 cm, offering a chance for subsurface organisms to undergo natural selection.
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Zou D, Liu H, Li M. Community, Distribution, and Ecological Roles of Estuarine Archaea. Front Microbiol 2020; 11:2060. [PMID: 32983044 PMCID: PMC7484942 DOI: 10.3389/fmicb.2020.02060] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 08/05/2020] [Indexed: 12/04/2022] Open
Abstract
Archaea are diverse and ubiquitous prokaryotes present in both extreme and moderate environments. Estuaries, serving as links between the land and ocean, harbor numerous microbes that are relatively highly active because of massive terrigenous input of nutrients. Archaea account for a considerable portion of the estuarine microbial community. They are diverse and play key roles in the estuarine biogeochemical cycles. Ammonia-oxidizing archaea (AOA) are an abundant aquatic archaeal group in estuaries, greatly contributing estuarine ammonia oxidation. Bathyarchaeota are abundant in sediments, and they may involve in sedimentary organic matter degradation, acetogenesis, and, potentially, methane metabolism, based on genomics. Other archaeal groups are also commonly detected in estuaries worldwide. They include Euryarchaeota, and members of the DPANN and Asgard archaea. Based on biodiversity surveys of the 16S rRNA gene and some functional genes, the distribution and abundance of estuarine archaea are driven by physicochemical factors, such as salinity and oxygen concentration. Currently, increasing amount of genomic information for estuarine archaea is becoming available because of the advances in sequencing technologies, especially for AOA and Bathyarchaeota, leading to a better understanding of their functions and environmental adaptations. Here, we summarized the current knowledge on the community composition and major archaeal groups in estuaries, focusing on AOA and Bathyarchaeota. We also highlighted the unique genomic features and potential adaptation strategies of estuarine archaea, pointing out major unknowns in the field and scope for future research.
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Affiliation(s)
- Dayu Zou
- SZU-HKUST Joint Ph.D. Program in Marine Environmental Science, Shenzhen University, Shenzhen, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, China
- Department of Ocean Science, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Hongbin Liu
- Department of Ocean Science, The Hong Kong University of Science and Technology, Hong Kong, China
- Hong Kong Branch of Southern Marine Science & Engineering Guangdong Laboratory, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Meng Li
- SZU-HKUST Joint Ph.D. Program in Marine Environmental Science, Shenzhen University, Shenzhen, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, China
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Diversity, ecology and evolution of Archaea. Nat Microbiol 2020; 5:887-900. [PMID: 32367054 DOI: 10.1038/s41564-020-0715-z] [Citation(s) in RCA: 194] [Impact Index Per Article: 48.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Accepted: 03/30/2020] [Indexed: 12/23/2022]
Abstract
Compared to bacteria, our knowledge of archaeal biology is limited. Historically, microbiologists have mostly relied on culturing and single-gene diversity surveys to understand Archaea in nature. However, only six of the 27 currently proposed archaeal phyla have cultured representatives. Advances in genomic sequencing and computational approaches are revolutionizing our understanding of Archaea. The recovery of genomes belonging to uncultured groups from the environment has resulted in the description of several new phyla, many of which are globally distributed and are among the predominant organisms on the planet. In this Review, we discuss how these genomes, together with long-term enrichment studies and elegant in situ measurements, are providing insights into the metabolic capabilities of the Archaea. We also debate how such studies reveal how important Archaea are in mediating an array of ecological processes, including global carbon and nutrient cycles, and how this increase in archaeal diversity has expanded our view of the tree of life and early archaeal evolution, and has provided new insights into the origin of eukaryotes.
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Compte-Port S, Fillol M, Gich F, Borrego CM. Metabolic versatility of freshwater sedimentary archaea feeding on different organic carbon sources. PLoS One 2020; 15:e0231238. [PMID: 32267873 PMCID: PMC7141681 DOI: 10.1371/journal.pone.0231238] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Accepted: 03/19/2020] [Indexed: 12/25/2022] Open
Abstract
Members of the phylum Bathyarchaeota and the class Thermoplasmata are widespread in marine and freshwater sediments where they have been recognized as key players in the carbon cycle. Here, we tested the responsiveness of archaeal communities on settled plant debris and sediment from a karstic lake to different organic carbon amendments (amino acids, plant-derived carbohydrates, and aromatics) using a lab-scale microcosm. Changes in the composition and abundance of sediment and biofilm archaeal communities in both DNA and RNA fractions were assessed by 16S rRNA gene amplicon sequencing and qPCR, respectively, after 7 and 30 days of incubation. Archaeal communities showed compositional changes in terms of alpha and beta diversity in relation to the type of carbon source (amino acids vs. plant-derived compounds), the nucleic acid fraction (DNA vs. RNA), and the incubation time (7 vs. 30 days). Distinct groups within the Bathyarchaeota (Bathy-15 and Bathy-6) and the Thermoplasmata (MBG-D) differently reacted to carbon supplements as deduced from the analysis of RNA libraries. Whereas Bathyarchaeota in biofilms showed a long-term positive response to humic acids, their counterparts in the sediment were mainly stimulated by the addition of tryptophan, suggesting the presence of different subpopulations in both habitats. Overall, our work presents an in vitro assessment of the versatility of archaea inhabiting freshwater sediments towards organic carbon and introduces settled leaf litter as a new habitat for the Bathyarchaeota and the Thermoplasmata.
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Affiliation(s)
- Sergi Compte-Port
- Water Quality and Microbial Diversity, Catalan Institute for Water Research (ICRA), Scientific and Technological Park of the University of Girona, Girona, Spain
| | - Mireia Fillol
- Water Quality and Microbial Diversity, Catalan Institute for Water Research (ICRA), Scientific and Technological Park of the University of Girona, Girona, Spain
| | - Frederic Gich
- Group of Molecular Microbial Ecology, Institute of Aquatic Ecology, University of Girona, Girona, Spain
| | - Carles M. Borrego
- Water Quality and Microbial Diversity, Catalan Institute for Water Research (ICRA), Scientific and Technological Park of the University of Girona, Girona, Spain
- Group of Molecular Microbial Ecology, Institute of Aquatic Ecology, University of Girona, Girona, Spain
- * E-mail:
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Pan J, Zhou Z, Béjà O, Cai M, Yang Y, Liu Y, Gu JD, Li M. Genomic and transcriptomic evidence of light-sensing, porphyrin biosynthesis, Calvin-Benson-Bassham cycle, and urea production in Bathyarchaeota. MICROBIOME 2020; 8:43. [PMID: 32234071 PMCID: PMC7110647 DOI: 10.1186/s40168-020-00820-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2019] [Accepted: 03/02/2020] [Indexed: 05/19/2023]
Abstract
BACKGROUND Bathyarchaeota, a newly proposed archaeal phylum, is considered as an important driver of the global carbon cycle. However, due to the great diversity of them, there is limited genomic information that accurately encompasses the metabolic potential of the entire archaeal phylum. RESULTS In the current study, nine metagenome-assembled genomes of Bathyarchaeota from four subgroups were constructed from mangrove sediments, and metatranscriptomes were obtained for evaluating their in situ transcriptional activities. Comparative analyses with reference genomes and the transcripts of functional genes posit an expanded role for Bathyarchaeota in phototrophy, autotrophy, and nitrogen and sulfur cycles, respectively. Notably, the presence of genes for rhodopsins, cobalamin biosynthesis, and the oxygen-dependent metabolic pathways in some Bathyarchaeota subgroup 6 genomes suggest a light-sensing and microoxic lifestyle within this subgroup. CONCLUSIONS The results of this study expand our knowledge of metabolic abilities and diverse lifestyles of Bathyarchaeota, highlighting the crucial role of Bathyarchaeota in geochemical cycle. Video abstract.
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Affiliation(s)
- Jie Pan
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, China
| | - Zhichao Zhou
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, China
- Laboratory of Environmental Microbiology and Toxicology, School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong, SAR China
| | - Oded Béjà
- Faculty of Biology, Technion-Israel Institute of Technology, 32000 Haifa, Israel
| | - Mingwei Cai
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, China
| | - Yuchun Yang
- Laboratory of Environmental Microbiology and Toxicology, School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong, SAR China
| | - Yang Liu
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, China
| | - Ji-Dong Gu
- Laboratory of Environmental Microbiology and Toxicology, School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong, SAR China
| | - Meng Li
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, China
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Zou D, Pan J, Liu Z, Zhang C, Liu H, Li M. The Distribution of Bathyarchaeota in Surface Sediments of the Pearl River Estuary Along Salinity Gradient. Front Microbiol 2020; 11:285. [PMID: 32174899 PMCID: PMC7056671 DOI: 10.3389/fmicb.2020.00285] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2019] [Accepted: 02/07/2020] [Indexed: 01/05/2023] Open
Abstract
Bathyarchaeota, a recently proposed archaeal phylum, is globally distributed and highly abundant in anoxic sediments. Metabolic pathways of the Bathyarchaeota members are diverse and, hence, this phylum has been proposed to play an important role in global biogeochemical cycles. Bathyarchaeota members are distributed in the estuarine environments. However, limited information is available about their detailed community structure, abundance, and functions in the Pearl River estuary (PRE). In the current study, we performed a comprehensive investigation of the archaeal community in the PRE surface sediments along a salinity gradient, with a focus on Bathyarchaeota. Bathyarchaeota was the dominant archaeal phylum, with the abundance of the bathyarchaeotal 16S rRNA gene ranging from 1.43 × 108 to 1.22 × 109 copies/g sediment dry weight (d.w.), and Bathy-8 was the dominant subgroup. Thaumarchaeota, Lokiarchaeota, and Euryarchaeota, including Thermoprofundales (MBG-D archaea), were the other major archaeal groups in the PRE. The differences of community distributions in the high- and low-salinity sediments were hence investigated. Statistical analysis revealed that besides salinity, ammonium, and total organic carbon were the most important environmental factors influencing the archaea community structure, including that of Bathyarchaeota, in the PRE. The archaeal network indicated the cooccurrence among Bathyarchaeota, Lokiarchaeota, and Euryarchaeota, while Bathy-6 presented unique correlations compared with other bathyarchaeotal subgroups. These observations indicate that Bathyarchaeota may play a role in ecosystem function through microbe-microbe interactions, revealing a possible different lifestyle for Bathy-6 in eutrophic estuarine sediments.
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Affiliation(s)
- Dayu Zou
- SZU-HKUST Joint Ph.D. Program in Marine Environmental Science, Institute for Advanced Study, Shenzhen University, Shenzhen, China
- Department of Ocean Science, The Hong Kong University of Science and Technology, Hong Kong, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, China
| | - Jie Pan
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, China
| | - Zongbao Liu
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, China
| | - Chuanlun Zhang
- Shenzhen Key Laboratory of Marine Archaea Geo-Omics, Southern University of Science and Technology, Shenzhen, China
| | - Hongbin Liu
- Department of Ocean Science, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Meng Li
- SZU-HKUST Joint Ph.D. Program in Marine Environmental Science, 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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Metabolic potentials of archaeal lineages resolved from metagenomes of deep Costa Rica sediments. ISME JOURNAL 2020; 14:1345-1358. [PMID: 32066876 DOI: 10.1038/s41396-020-0615-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 01/30/2020] [Accepted: 02/07/2020] [Indexed: 02/06/2023]
Abstract
Numerous archaeal lineages are known to inhabit marine subsurface sediments, although their distributions, metabolic capacities, and interspecies interactions are still not well understood. Abundant and diverse archaea were recently reported in Costa Rica (CR) margin subseafloor sediments recovered during IODP Expedition 334. Here, we recover metagenome-assembled genomes (MAGs) of archaea from the CR margin and compare them to their relatives from shallower settings. We describe 31 MAGs of six different archaeal lineages (Lokiarchaeota, Thorarchaeota, Heimdallarchaeota, Bathyarcheota, Thermoplasmatales, and Hadesarchaea) and thoroughly analyze representative MAGs from the phyla Lokiarchaeota and Bathyarchaeota. Our analysis suggests the potential capability of Lokiarchaeota members to anaerobically degrade aliphatic and aromatic hydrocarbons. We show it is genetically possible and energetically feasible for Lokiarchaeota to degrade benzoate if they associate with organisms using nitrate, nitrite, and sulfite as electron acceptors, which suggests a possibility of syntrophic relationships between Lokiarchaeota and nitrite and sulfite reducing bacteria. The novel Bathyarchaeota lineage possesses an incomplete methanogenesis pathway lacking the methyl coenzyme M reductase complex and encodes a noncanonical acetogenic pathway potentially coupling methylotrophy to acetogenesis via the methyl branch of Wood-Ljungdahl pathway. These metabolic characteristics suggest the potential of this Bathyarchaeota lineage to be a transition between methanogenic and acetogenic Bathyarchaeota lineages. This work expands our knowledge about the metabolic functional repertoire of marine benthic archaea.
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Wang W, Tao J, Liu H, Li P, Chen S, Wang P, Zhang C. Contrasting bacterial and archaeal distributions reflecting different geochemical processes in a sediment core from the Pearl River Estuary. AMB Express 2020; 10:16. [PMID: 31970539 PMCID: PMC6975606 DOI: 10.1186/s13568-020-0950-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Accepted: 01/06/2020] [Indexed: 01/27/2023] Open
Abstract
Microbial community structure and metabolic activities have profound impacts on biogeochemical processes in marine sediments. Functional bacteria such as nitrate- and sulfate-reducing bacteria respond to redox gradients by coupling specific reactions amenable to relevant energy metabolisms. However, similar functional patterns have not been observed for sedimentary archaea (except for anaerobic methanotrophs and methanogens). We coupled taxonomic composition with comprehensive geochemical species to investigate the participation of distinct bacteria and archaea in sedimentary geochemical cycles in a sediment core (300 cm) from Pearl River Estuary (PRE). Geochemical properties (NO3−, dissolved Mn and Fe, SO42+, NH4+; dissolved inorganic carbon (DIC), δ13CDIC, dissolved organic carbon (DOC), total organic carbon (TOC), δ13CTOC, and fluorescent dissolved organic matter (FDOM)) exhibited strong depth variability of different trends. Bacterial 16S rRNA- and dsrB gene abundance decreased sharply with depth while archaeal and bathyarchaeotal 16S rRNA gene copies were relatively constant. This resulted in an increase in relative abundance of archaea from surface (11.6%) to bottom (42.8%). Network analysis showed that bacterial groups of Desulfobacterales, Syntrophobacterales and Gammaproteobacteria were significantly (P < 0.0001) associated with SO42− and dissolved Mn while archaeal groups of Bathyarchaeota, Group C3 and Marine Benthic Group D (MBGD) showed close positive correlations (P < 0.0001) with NH4+, δ13CTOC values and humic-like FDOM. Our study suggested that these bacterial groups dominated in redox processes relevant to sulfate or metal oxides, while the archaeal groups are more like to degrade recalcitrant organic compounds in anaerobic sediments.
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Kinetics and Identities of Extracellular Peptidases in Subsurface Sediments of the White Oak River Estuary, North Carolina. Appl Environ Microbiol 2019; 85:AEM.00102-19. [PMID: 31324636 PMCID: PMC6752024 DOI: 10.1128/aem.00102-19] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 07/14/2019] [Indexed: 11/20/2022] Open
Abstract
Anoxic subsurface sediments contain communities of heterotrophic microorganisms that metabolize organic carbon at extraordinarily low rates. In order to assess the mechanisms by which subsurface microorganisms access detrital sedimentary organic matter, we measured kinetics of a range of extracellular peptidases in anoxic sediments of the White Oak River Estuary, NC. Nine distinct peptidase substrates were enzymatically hydrolyzed at all depths. Potential peptidase activities (V max) decreased with increasing sediment depth, although V max expressed on a per-cell basis was approximately the same at all depths. Half-saturation constants (Km ) decreased with depth, indicating peptidases that functioned more efficiently at low substrate concentrations. Potential activities of extracellular peptidases acting on molecules that are enriched in degraded organic matter (d-phenylalanine and l-ornithine) increased relative to enzymes that act on l-phenylalanine, further suggesting microbial community adaptation to access degraded organic matter. Nineteen classes of predicted, exported peptidases were identified in genomic data from the same site, of which genes for class C25 (gingipain-like) peptidases represented more than 40% at each depth. Methionine aminopeptidases, zinc carboxypeptidases, and class S24-like peptidases, which are involved in single-stranded-DNA repair, were also abundant. These results suggest a subsurface heterotrophic microbial community that primarily accesses low-quality detrital organic matter via a diverse suite of well-adapted extracellular enzymes.IMPORTANCE Burial of organic carbon in marine and estuarine sediments represents a long-term sink for atmospheric carbon dioxide. Globally, ∼40% of organic carbon burial occurs in anoxic estuaries and deltaic systems. However, the ultimate controls on the amount of organic matter that is buried in sediments, versus oxidized into CO2, are poorly constrained. In this study, we used a combination of enzyme assays and metagenomic analysis to identify how subsurface microbial communities catalyze the first step of proteinaceous organic carbon degradation. Our results show that microbial communities in deeper sediments are adapted to access molecules characteristic of degraded organic matter, suggesting that those heterotrophs are adapted to life in the subsurface.
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