1
|
Zhang C, Fang YX, Yin X, Lai H, Kuang Z, Zhang T, Xu XP, Wegener G, Wang JH, Dong X. The majority of microorganisms in gas hydrate-bearing subseafloor sediments ferment macromolecules. MICROBIOME 2023; 11:37. [PMID: 36864529 PMCID: PMC9979476 DOI: 10.1186/s40168-023-01482-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Accepted: 01/30/2023] [Indexed: 06/01/2023]
Abstract
BACKGROUND Gas hydrate-bearing subseafloor sediments harbor a large number of microorganisms. Within these sediments, organic matter and upward-migrating methane are important carbon and energy sources fueling a light-independent biosphere. However, the type of metabolism that dominates the deep subseafloor of the gas hydrate zone is poorly constrained. Here we studied the microbial communities in gas hydrate-rich sediments up to 49 m below the seafloor recovered by drilling in the South China Sea. We focused on distinct geochemical conditions and performed metagenomic and metatranscriptomic analyses to characterize microbial communities and their role in carbon mineralization. RESULTS Comparative microbial community analysis revealed that samples above and in sulfate-methane interface (SMI) zones were clearly distinguished from those below the SMI. Chloroflexota were most abundant above the SMI, whereas Caldatribacteriota dominated below the SMI. Verrucomicrobiota, Bathyarchaeia, and Hadarchaeota were similarly present in both types of sediment. The genomic inventory and transcriptional activity suggest an important role in the fermentation of macromolecules. In contrast, sulfate reducers and methanogens that catalyze the consumption or production of commonly observed chemical compounds in sediments are rare. Methanotrophs and alkanotrophs that anaerobically grow on alkanes were also identified to be at low abundances. The ANME-1 group actively thrived in or slightly below the current SMI. Members from Heimdallarchaeia were found to encode the potential for anaerobic oxidation of short-chain hydrocarbons. CONCLUSIONS These findings indicate that the fermentation of macromolecules is the predominant energy source for microorganisms in deep subseafloor sediments that are experiencing upward methane fluxes. Video Abstract.
Collapse
Affiliation(s)
- Chuwen Zhang
- School of Marine Sciences, Sun Yat-Sen University, Zhuhai, China
- Key Laboratory of Marine Genetic Resources, Third Institute of Oceanography, Ministry of Natural Resources, Xiamen, China
| | - Yun-Xin Fang
- Guangzhou Marine Geological Survey, China Geological Survey, Ministry of Natural Resources, Guangzhou, China
| | - Xiuran Yin
- Faculty of Biology/Chemistry, University of Bremen, Bremen, Germany
- MARUM, Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
- Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Hongfei Lai
- Guangzhou Marine Geological Survey, China Geological Survey, Ministry of Natural Resources, Guangzhou, China
| | - Zenggui Kuang
- Guangzhou Marine Geological Survey, China Geological Survey, Ministry of Natural Resources, Guangzhou, China
| | - Tianxueyu Zhang
- School of Marine Sciences, Sun Yat-Sen University, Zhuhai, China
| | - Xiang-Po Xu
- School of Marine Sciences, Sun Yat-Sen University, Zhuhai, China
| | - Gunter Wegener
- MARUM, Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
- Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Jiang-Hai Wang
- School of Marine Sciences, Sun Yat-Sen University, Zhuhai, China.
| | - Xiyang Dong
- Key Laboratory of Marine Genetic Resources, Third Institute of Oceanography, Ministry of Natural Resources, Xiamen, China.
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China.
| |
Collapse
|
2
|
Niu M, Deng L, Su L, Ruff SE, Yang N, Luo M, Qi Q, Li J, Wang F. Methane supply drives prokaryotic community assembly and networks at cold seeps of the South China Sea. Mol Ecol 2023; 32:660-679. [PMID: 36408814 DOI: 10.1111/mec.16786] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Revised: 10/10/2022] [Accepted: 11/01/2022] [Indexed: 11/22/2022]
Abstract
Marine cold seeps are unique chemosynthetic habitats fuelled by deeply sourced hydrocarbon-rich fluids discharged at the seafloor. Through oxidizing methane and other hydrocarbons, microorganisms inhabiting cold seeps supply subsurface-derived energy to higher trophic levels, sustaining highly productive oases of life in the deep sea. Despite the central role of microbiota in mediating biogeochemical cycles, the factors that govern the assembly and network of prokaryotic communities in cold seeps remain poorly understood. Here we analysed the geochemical and microbiological profiles of 11 different sediment cores from two spatially distant cold seeps of the South China Sea. We show that prokaryotic communities belonging to the same methane-supply regimes (high-methane-supply, low-methane-supply and non-seep control sediments) had a highly similar community structure, regardless of geographical location, seep-associated biota (mussel, clam, microbial mat) and sediment depth. Methane supply appeared to drive the niche partitioning of anaerobic methanotrophic archaea (ANME) at the regional scale, with ANME-1 accounting for >60% sequence abundance of ANME in the high-methane-supply sediments, while ANME-2 dominated (>90%) the low-methane-supply sediments. Increasing methane supply enhanced the contribution of environmental selection but lessened the contributions of dispersal limitation and drift to overall community assembly. High methane supply, moreover, promoted a more tightly connected, less stable prokaryotic network dominated by positive correlations. Together, these results provide a potentially new framework for understanding the niches and network interplay of prokaryotic communities across different methane seepage regimes in cold-seep sediments.
Collapse
Affiliation(s)
- Mingyang Niu
- 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
| | - Longhui Deng
- School of Oceanography, Shanghai Jiao Tong University, Shanghai, China
| | - Lei Su
- State Key Laboratory of Marine Geology, Tongji University, Shanghai, China
| | - S Emil Ruff
- Ecosystems Center and Josephine Bay Paul Center, Marine Biological Laboratory, Woods Hole, Massachusetts, USA
| | - Na Yang
- School of Oceanography, Shanghai Jiao Tong University, Shanghai, China
| | - Min Luo
- Shanghai Engineering Research Center of Hadal Science and Technology, College of Marine Sciences, Shanghai Ocean University, Shanghai, China
| | - Qi Qi
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Jiangtao Li
- State Key Laboratory of Marine Geology, Tongji University, Shanghai, China
| | - 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
| |
Collapse
|
3
|
Vulcano F, Hahn CJ, Roerdink D, Dahle H, Reeves EP, Wegener G, Steen IH, Stokke R. Phylogenetic and functional diverse ANME-1 thrive in Arctic hydrothermal vents. FEMS Microbiol Ecol 2022; 98:6747120. [PMID: 36190327 PMCID: PMC9576274 DOI: 10.1093/femsec/fiac117] [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: 02/12/2022] [Revised: 09/15/2022] [Accepted: 09/29/2022] [Indexed: 01/21/2023] Open
Abstract
The methane-rich areas, the Loki's Castle vent field and the Jan Mayen vent field at the Arctic Mid Ocean Ridge (AMOR), host abundant niches for anaerobic methane-oxidizers, which are predominantly filled by members of the ANME-1. In this study, we used a metagenomic-based approach that revealed the presence of phylogenetic and functional different ANME-1 subgroups at AMOR, with heterogeneous distribution. Based on a common analysis of ANME-1 genomes from AMOR and other geographic locations, we observed that AMOR subgroups clustered with a vent-specific ANME-1 group that occurs solely at vents, and with a generalist ANME-1 group, with a mixed environmental origin. Generalist ANME-1 are enriched in genes coding for stress response and defense strategies, suggesting functional diversity among AMOR subgroups. ANME-1 encode a conserved energy metabolism, indicating strong adaptation to sulfate-methane-rich sediments in marine systems, which does not however prevent global dispersion. A deep branching family named Ca. Veteromethanophagaceae was identified. The basal position of vent-related ANME-1 in phylogenomic trees suggests that ANME-1 originated at hydrothermal vents. The heterogeneous and variable physicochemical conditions present in diffuse venting areas of hydrothermal fields could have favored the diversification of ANME-1 into lineages that can tolerate geochemical and environmental variations.
Collapse
Affiliation(s)
- F Vulcano
- Corresponding author: Thormølens gate 53 A 5006 Bergen Postboks 7803 5020 Bergen. E-mail:
| | - C J Hahn
- Max-Plank Institute for Marine Microbiology, HGF MPG Joint Research Group for Deep-Sea Ecology and Technology, Bremen, 28359, Germany
| | - D Roerdink
- Department of Earth Science, Center for Deep Sea Research, University of Bergen, Bergen, Norway
| | - H Dahle
- Computational Biological Unit, Department of Informatics, Department of Biological Sciences, Center for Deep Sea Research, University of Bergen, Bergen, Norway
| | - E P Reeves
- Department of Earth Science, Center for Deep Sea Research, University of Bergen, Bergen, Norway
| | - G Wegener
- Max-Plank Institute for Marine Microbiology, HGF MPG Joint Research Group for Deep-Sea Ecology and Technology, Bremen, 28359, Germany,MARUM, Center for Marine Environmental Sciences, University Bremen, Bremen, 28359, Germany,Alfred Wegener Institute Helmholtz Center for Polar and Marine Research, Bremerhaven, 27570, Germany
| | - I H Steen
- Department of Biological Sciences, Center for Deep Sea Research, University of Bergen, Bergen, Norway
| | - R Stokke
- Corresponding author: Thormølens gate 53 A 5006 Bergen Postboks 7803 5020 Bergen. E-mail:
| |
Collapse
|
4
|
Shi LD, Zhou YJ, Tang XJ, Kappler A, Chistoserdova L, Zhu LZ, Zhao HP. Coupled Aerobic Methane Oxidation and Arsenate Reduction Contributes to Soil-Arsenic Mobilization in Agricultural Fields. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:11845-11856. [PMID: 35920083 DOI: 10.1021/acs.est.2c01878] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Microbial oxidation of organic compounds can promote arsenic release by reducing soil-associated arsenate to the more mobile form arsenite. While anaerobic oxidation of methane has been demonstrated to reduce arsenate, it remains elusive whether and to what extent aerobic methane oxidation (aeMO) can contribute to reductive arsenic mobilization. To fill this knowledge gap, we performed incubations of both microbial laboratory cultures and soil samples from arsenic-contaminated agricultural fields in China. Incubations with laboratory cultures showed that aeMO could couple to arsenate reduction, wherein the former bioprocess was carried out by aerobic methanotrophs and the latter by a non-methanotrophic bacterium belonging to a novel and uncultivated representative of Burkholderiaceae. Metagenomic analyses combined with metabolite measurements suggested that formate served as the interspecies electron carrier linking aeMO to arsenate reduction. Such coupled bioprocesses also take place in the real world, supported by a similar stoichiometry and gene activity in the incubations with natural paddy soils, and contribute up to 76.2% of soil-arsenic mobilization into pore waters in the top layer of the soils where oxygen was present. Overall, this study reveals a previously overlooked yet significant contribution of aeMO to reductive arsenic mobilization.
Collapse
Affiliation(s)
- Ling-Dong Shi
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yu-Jie Zhou
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Xian-Jin Tang
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Andreas Kappler
- Center for Applied Geosciences, University of Tübingen, Tübingen 72074, Germany
| | - Ludmila Chistoserdova
- Department of Chemical Engineering, University of Washington, Seattle, Washington 98195-0005, United States
| | - Li-Zhong Zhu
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - He-Ping Zhao
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| |
Collapse
|
5
|
Community Structure and Microbial Associations in Sediment-Free Methanotrophic Enrichment Cultures from a Marine Methane Seep. Appl Environ Microbiol 2022; 88:e0210921. [PMID: 35604226 DOI: 10.1128/aem.02109-21] [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] [Indexed: 01/04/2023] Open
Abstract
Syntrophic consortia of anaerobic methanotrophic archaea (ANME) and sulfate-reducing bacteria (SRB) consume large amounts of methane and serve as the foundational microorganisms in marine methane seeps. Despite their importance in the carbon cycle, research on the physiology of ANME-SRB consortia has been hampered by the slow growth and complex physicochemical environment the consortia inhabit. Here, we report successful sediment-free enrichment of ANME-SRB consortia from deep-sea methane seep sediments in the Santa Monica Basin, California. Anoxic Percoll density gradients and size-selective filtration were used to separate ANME-SRB consortia from sediment particles and single cells to accelerate the cultivation process. Over a 3-year period, a subset of the sediment-associated ANME and SRB lineages, predominantly comprised of ANME-2a/2b ("Candidatus Methanocomedenaceae") and their syntrophic bacterial partners, SEEP-SRB1/2, adapted and grew under defined laboratory conditions. Metagenome-assembled genomes from several enrichments revealed that ANME-2a, SEEP-SRB1, and Methanococcoides in different enrichments from the same inoculum represented distinct species, whereas other coenriched microorganisms were closely related at the species level. This suggests that ANME, SRB, and Methanococcoides are more genetically diverse than other members in methane seeps. Flow cytometry sorting and sequencing of cell aggregates revealed that Methanococcoides, Anaerolineales, and SEEP-SRB1 were overrepresented in multiple ANME-2a cell aggregates relative to the bulk metagenomes, suggesting they were physically associated and possibly interacting. Overall, this study represents a successful case of selective cultivation of anaerobic slow-growing microorganisms from sediments based on their physical characteristics, introducing new opportunities for detailed genomic, physiological, biochemical, and ecological analyses. IMPORTANCE Biological anaerobic oxidation of methane (AOM) coupled with sulfate reduction represents a large methane sink in global ocean sediments. Methane consumption is carried out by syntrophic archaeal-bacterial consortia and fuels a unique ecosystem, yet the interactions in these slow-growing syntrophic consortia and with other associated community members remain poorly understood. The significance of this study is the establishment of sediment-free enrichment cultures of anaerobic methanotrophic archaea and sulfate-reducing bacteria performing AOM with sulfate using selective cultivation approaches based on size, density, and metabolism. By reconstructing microbial genomes and analyzing community composition of the enrichment cultures and cell aggregates, we shed light on the diversity of microorganisms physically associated with AOM consortia beyond the core syntrophic partners. These enrichment cultures offer simplified model systems to extend our understanding of the diversity of microbial interactions within marine methane seeps.
Collapse
|
6
|
Mohr W, Lehnen N, Ahmerkamp S, Marchant HK, Graf JS, Tschitschko B, Yilmaz P, Littmann S, Gruber-Vodicka H, Leisch N, Weber M, Lott C, Schubert CJ, Milucka J, Kuypers MMM. Terrestrial-type nitrogen-fixing symbiosis between seagrass and a marine bacterium. Nature 2021; 600:105-109. [PMID: 34732889 PMCID: PMC8636270 DOI: 10.1038/s41586-021-04063-4] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 09/22/2021] [Indexed: 01/23/2023]
Abstract
Symbiotic N2-fixing microorganisms have a crucial role in the assimilation of nitrogen by eukaryotes in nitrogen-limited environments1-3. Particularly among land plants, N2-fixing symbionts occur in a variety of distantly related plant lineages and often involve an intimate association between host and symbiont2,4. Descriptions of such intimate symbioses are lacking for seagrasses, which evolved around 100 million years ago from terrestrial flowering plants that migrated back to the sea5. Here we describe an N2-fixing symbiont, 'Candidatus Celerinatantimonas neptuna', that lives inside seagrass root tissue, where it provides ammonia and amino acids to its host in exchange for sugars. As such, this symbiosis is reminiscent of terrestrial N2-fixing plant symbioses. The symbiosis between Ca. C. neptuna and its host Posidonia oceanica enables highly productive seagrass meadows to thrive in the nitrogen-limited Mediterranean Sea. Relatives of Ca. C. neptuna occur worldwide in coastal ecosystems, in which they may form similar symbioses with other seagrasses and saltmarsh plants. Just like N2-fixing microorganisms might have aided the colonization of nitrogen-poor soils by early land plants6, the ancestors of Ca. C. neptuna and its relatives probably enabled flowering plants to invade nitrogen-poor marine habitats, where they formed extremely efficient blue carbon ecosystems7.
Collapse
Affiliation(s)
- Wiebke Mohr
- Max Planck Institute for Marine Microbiology, Bremen, Germany.
| | - Nadine Lehnen
- Max Planck Institute for Marine Microbiology, Bremen, Germany
| | | | | | - Jon S Graf
- Max Planck Institute for Marine Microbiology, Bremen, Germany
| | | | - Pelin Yilmaz
- Max Planck Institute for Marine Microbiology, Bremen, Germany
- Data Science Research Group, Institute for Artificial Intelligence in Medicine, University Hospital Essen, Essen, Germany
| | - Sten Littmann
- Max Planck Institute for Marine Microbiology, Bremen, Germany
| | | | - Nikolaus Leisch
- Max Planck Institute for Marine Microbiology, Bremen, Germany
| | | | | | - Carsten J Schubert
- Swiss Federal Institute of Aquatic Science and Technology (Eawag), Department of Surface Waters-Research and Management, Kastanienbaum, Switzerland
| | - Jana Milucka
- Max Planck Institute for Marine Microbiology, Bremen, Germany
| | | |
Collapse
|
7
|
Shi LD, Wang Z, Liu T, Wu M, Lai CY, Rittmann BE, Guo J, Zhao HP. Making good use of methane to remove oxidized contaminants from wastewater. WATER RESEARCH 2021; 197:117082. [PMID: 33819663 DOI: 10.1016/j.watres.2021.117082] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 03/13/2021] [Accepted: 03/20/2021] [Indexed: 06/12/2023]
Abstract
Being an energetic fuel, methane is able to support microbial growth and drive the reduction of various electron acceptors. These acceptors include a broad range of oxidized contaminants (e.g., nitrate, nitrite, perchlorate, bromate, selenate, chromate, antimonate and vanadate) that are ubiquitously detected in water environments and pose threats to human and ecological health. Using methane as electron donor to biologically reduce these contaminants into nontoxic forms is a promising solution to remediate polluted water, considering that methane is a widely available and inexpensive electron donor. The understanding of methane-based biological reduction processes and the responsible microorganisms has grown in the past decade. This review summarizes the fundamentals of metabolic pathways and microorganisms mediating microbial methane oxidation. Experimental demonstrations of methane as an electron donor to remove oxidized contaminants are summarized, compared, and evaluated. Finally, the review identifies opportunities and unsolved questions that deserve future explorations for broadening understanding of methane oxidation and promoting its practical applications.
Collapse
Affiliation(s)
- Ling-Dong Shi
- College of Environmental and Resource Science, Zhejiang University, Hangzhou, Zhejiang, China; Zhejiang Province Key Lab Water Pollution Control & Environment, Zhejiang University, Hangzhou, Zhejiang, China
| | - Zhen Wang
- College of Environmental and Resource Science, Zhejiang University, Hangzhou, Zhejiang, China; Zhejiang Province Key Lab Water Pollution Control & Environment, Zhejiang University, Hangzhou, Zhejiang, China
| | - Tao Liu
- Advanced Water Management Centre, The University of Queensland, St Lucia, Brisbane, Queensland 4072, Australia
| | - Mengxiong Wu
- Advanced Water Management Centre, The University of Queensland, St Lucia, Brisbane, Queensland 4072, Australia
| | - Chun-Yu Lai
- Advanced Water Management Centre, The University of Queensland, St Lucia, Brisbane, Queensland 4072, Australia
| | - Bruce E Rittmann
- Biodesign Swette Center for Environmental Biotechnology, Arizona State University, P.O. Box 875701, Tempe, Arizona 85287-5701, U.S.A
| | - Jianhua Guo
- Advanced Water Management Centre, The University of Queensland, St Lucia, Brisbane, Queensland 4072, Australia.
| | - He-Ping Zhao
- College of Environmental and Resource Science, Zhejiang University, Hangzhou, Zhejiang, China; Zhejiang Province Key Lab Water Pollution Control & Environment, Zhejiang University, Hangzhou, Zhejiang, China.
| |
Collapse
|
8
|
Wang Y, Wegener G, Ruff SE, Wang F. Methyl/alkyl-coenzyme M reductase-based anaerobic alkane oxidation in archaea. Environ Microbiol 2020; 23:530-541. [PMID: 32367670 DOI: 10.1111/1462-2920.15057] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 04/28/2020] [Accepted: 04/30/2020] [Indexed: 02/04/2023]
Abstract
Methyl-coenzyme M reductase (MCR) has been originally identified to catalyse the final step of the methanogenesis pathway. About 20 years ago anaerobic methane-oxidizing archaea (ANME) were discovered that use MCR enzymes to activate methane. ANME thrive at the thermodynamic limit of life, are slow-growing, and in most cases form syntrophic consortia with sulfate-reducing bacteria. Recently, archaea that have the ability to anaerobically oxidize non-methane multi-carbon alkanes such as ethane and n-butane were described in both enrichment cultures and environmental samples. These anaerobic multi-carbon alkane-oxidizing archaea (ANKA) use enzymes homologous to MCR named alkyl-coenzyme M reductase (ACR). Here we review the recent progresses on the diversity, distribution and functioning of both ANME and ANKA by presenting a detailed MCR/ACR-based phylogeny, compare their metabolic pathways and discuss the gaps in our knowledge of physiology of these organisms. To improve our understanding of alkane oxidation in archaea, we identified three directions for future research: (i) expanding cultivation attempts to validate omics-based metabolic models of yet-uncultured organisms, (ii) performing biochemical and structural analyses of key enzymes to understand thermodynamic and steric constraints and (iii) investigating the evolution of anaerobic alkane metabolisms and their impact on biogeochemical cycles.
Collapse
Affiliation(s)
- Yinzhao Wang
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China.,State Key Laboratory of Ocean Engineering, School of Naval Architecture, Ocean & Civil Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Gunter Wegener
- Max Planck Institute for Marine Microbiology, Bremen, Germany.,MARUM, Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | - S Emil Ruff
- Ecosystems Center, Marine Biological Laboratory, Woods Hole, MA, USA.,J. Bay Paul Center for Comparative Molecular Biology and Evolution, Marine Biological Laboratory, Woods Hole, MA, USA
| | - 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.,Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, Guangdong, China
| |
Collapse
|
9
|
Cassarini C, Rene ER, Bhattarai S, Vogt C, Musat N, Lens PNL. Anaerobic methane oxidation coupled to sulfate reduction in a biotrickling filter: Reactor performance and microbial community analysis. CHEMOSPHERE 2019; 236:124290. [PMID: 31310977 DOI: 10.1016/j.chemosphere.2019.07.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 06/28/2019] [Accepted: 07/02/2019] [Indexed: 06/10/2023]
Abstract
The aim of this work was to evaluate the performance of a biotrickling filter (BTF) packed with polyurethane foam and pall rings for the enrichment of microorganisms mediating anaerobic oxidation of methane (AOM) coupled to sulfate reduction (SR) by activity tests and microbial community analysis. A BTF was inoculated with microorganisms from a known AOM active deep sea sediment collected at a depth of 528 m below the sea level (Alpha Mound, Gulf of Cadiz). The microbial community analysis was performed by catalyzed reporter deposition - fluorescence in situ hybridization (CARD-FISH) and 16S rRNA sequence analysis. The AOM occurrence and rates in the BTF were assessed by performing batch activity assays using 13C-labelled methane (13CH4). After an estimated start-up time of ∼20 days, AOM rates of ∼0.3 mmol l-1 day-1 were observed in the BTF, values almost 20 times higher than previously reported in a polyurethane foam packed BTF. The microbial community consisted mainly of anaerobic methanotrophs (ANME-2, 22% of the total number of cells) and sulfate reducing bacteria (SRB, 47% of the total number of cells). This study showed that the BTF is a suitable reactor configuration for the enrichment of microbial communities involved in AOM coupled to SR at ambient pressure and temperature with a relatively short start-up time.
Collapse
Affiliation(s)
- Chiara Cassarini
- UNESCO-IHE, Institute for Water Education, P. O. Box 3015, 2601, DA, Delft, the Netherlands; National University of Ireland Galway, University Road, Galway, H91 TK33, Ireland.
| | - Eldon R Rene
- UNESCO-IHE, Institute for Water Education, P. O. Box 3015, 2601, DA, Delft, the Netherlands
| | - Susma Bhattarai
- UNESCO-IHE, Institute for Water Education, P. O. Box 3015, 2601, DA, Delft, the Netherlands
| | - Carsten Vogt
- Helmholtz-Centre for Environmental Research - UFZ, Department of Isotope Biogeochemistry, Permoser Strasse 15, 04318, Leipzig, Germany
| | - Niculina Musat
- Helmholtz-Centre for Environmental Research - UFZ, Department of Isotope Biogeochemistry, Permoser Strasse 15, 04318, Leipzig, Germany
| | - Piet N L Lens
- UNESCO-IHE, Institute for Water Education, P. O. Box 3015, 2601, DA, Delft, the Netherlands; National University of Ireland Galway, University Road, Galway, H91 TK33, Ireland
| |
Collapse
|
10
|
Taubert M, Grob C, Crombie A, Howat AM, Burns OJ, Weber M, Lott C, Kaster AK, Vollmers J, Jehmlich N, von Bergen M, Chen Y, Murrell JC. Communal metabolism by Methylococcaceae and Methylophilaceae is driving rapid aerobic methane oxidation in sediments of a shallow seep near Elba, Italy. Environ Microbiol 2019; 21:3780-3795. [PMID: 31267680 DOI: 10.1111/1462-2920.14728] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Revised: 06/14/2019] [Accepted: 06/29/2019] [Indexed: 11/29/2022]
Abstract
The release of abiotic methane from marine seeps into the atmosphere is a major source of this potent greenhouse gas. Methanotrophic microorganisms in methane seeps use methane as carbon and energy source, thus significantly mitigating global methane emissions. Here, we investigated microbial methane oxidation at the sediment-water interface of a shallow marine methane seep. Metagenomics and metaproteomics, combined with 13 C-methane stable isotope probing, demonstrated that various members of the gammaproteobacterial family Methylococcaceae were the key players for methane oxidation, catalysing the first reaction step to methanol. We observed a transfer of carbon to methanol-oxidizing methylotrophs of the betaproteobacterial family Methylophilaceae, suggesting an interaction between methanotrophic and methylotrophic microorganisms that allowed for rapid methane oxidation. From our microcosms, we estimated methane oxidation rates of up to 871 nmol of methane per gram sediment per day. This implies that more than 50% of methane at the seep is removed by microbial oxidation at the sediment-water interface, based on previously reported in situ methane fluxes. The organic carbon produced was further assimilated by different heterotrophic microbes, demonstrating that the methane-oxidizing community supported a complex trophic network. Our results provide valuable eco-physiological insights into this specialized microbial community performing an ecosystem function of global relevance.
Collapse
Affiliation(s)
- Martin Taubert
- Aquatic Geomicrobiology, Institute of Biodiversity, Friedrich Schiller University Jena, Dornburger Str. 159 07743, Jena, Germany.,School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
| | - Carolina Grob
- School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
| | - Andrew Crombie
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
| | - Alexandra M Howat
- School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
| | - Oliver J Burns
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
| | - Miriam Weber
- HYDRA Marine Sciences GmbH, Sinzheim, Germany.,HYDRA Field Station Elba, Italy.,Microsensor Group, Max Plank Institute for Marine Microbiology, 28359, Celsiusstr. 1, Bremen, Germany
| | - Christian Lott
- HYDRA Marine Sciences GmbH, Sinzheim, Germany.,HYDRA Field Station Elba, Italy.,Department of Symbiosis, Max Plank Institute for Marine Microbiology, 28359, Celsiusstr. 1, Bremen, Germany
| | - Anne-Kristin Kaster
- Institute for Biological Interfaces (IBG5), Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Karlsruhe, Germany.,Leibniz Institute DSMZ - German Collection of Microorganisms and Cell Cultures, 38124, Inhoffenstrasse 7B, Braunschweig, Germany
| | - John Vollmers
- Institute for Biological Interfaces (IBG5), Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Karlsruhe, Germany.,Leibniz Institute DSMZ - German Collection of Microorganisms and Cell Cultures, 38124, Inhoffenstrasse 7B, Braunschweig, Germany
| | - Nico Jehmlich
- Department of Molecular Systems Biology, Helmholtz Centre for Environmental Research - UFZ, Leipzig, Germany
| | - Martin von Bergen
- Department of Molecular Systems Biology, Helmholtz Centre for Environmental Research - UFZ, Leipzig, Germany.,Institute of Biochemistry, Faculty of Biosciences, Pharmacy and Psychology, University of Leipzig, 04103, Brüderstraße 32, Leipzig, Germany.,Department of Chemistry and Bioscience, University of Aalborg, 9220, Fredrik Bajers Vej 7H, Aalborg East, Denmark
| | - Yin Chen
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
| | - John Colin Murrell
- School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
| |
Collapse
|
11
|
Meister P, Wiedling J, Lott C, Bach W, Kuhfuß H, Wegener G, Böttcher ME, Deusner C, Lichtschlag A, Bernasconi SM, Weber M. Anaerobic methane oxidation inducing carbonate precipitation at abiogenic methane seeps in the Tuscan archipelago (Italy). PLoS One 2018; 13:e0207305. [PMID: 30566474 PMCID: PMC6300204 DOI: 10.1371/journal.pone.0207305] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2018] [Accepted: 10/29/2018] [Indexed: 11/21/2022] Open
Abstract
Seepage of methane (CH4) on land and in the sea may significantly affect Earth's biogeochemical cycles. However processes of CH4 generation and consumption, both abiotic and microbial, are not always clear. We provide new geochemical and isotope data to evaluate if a recently discovered CH4 seepage from the shallow seafloor close to the Island of Elba (Tuscany) and two small islands nearby are derived from abiogenic or biogenic sources and whether carbonate encrusted vents are the result of microbial or abiotic processes. Emission of gas bubbles (predominantly CH4) from unlithified sands was observed at seven spots in an area of 100 m2 at Pomonte (Island of Elba), with a total rate of 234 ml m-2 d-1. The measured carbon isotope values of CH4 of around -18‰ (VPDB) in combination with the measured δ2H value of -120‰ (VSMOW) and the inverse correlation of δ13C-value with carbon number of hydrocarbon gases are characteristic for sites of CH4 formation through abiogenic processes, specifically abiogenic formation of CH4 via reduction of CO2 by H2. The H2 for methanogenesis likely derives from ophiolitic host rock within the Ligurian accretionary prism. The lack of hydrothermal activity allows CH4 gas to become decoupled from the stagnant aqueous phase. Hence no hyperalkaline fluid is currently released at the vent sites. Within the seep area a decrease in porewater sulphate concentrations by ca. 5 mmol/l relative to seawater and a concomitant increase in sulphide and dissolved inorganic carbon (DIC) indicate substantial activity of sulphate-dependent anaerobic oxidation of methane (AOM). In absence of any other dissimilatory pathway, the δ13C-values between -17 and -5‰ in dissolved inorganic carbon and aragonite cements suggest that the inorganic carbon is largely derived from CH4. The formation of seep carbonates is thus microbially induced via anaerobic oxidation of abiotic CH4.
Collapse
Affiliation(s)
- Patrick Meister
- Department of Geodynamics and Sedimentology, University of Vienna, Vienna, Austria
| | - Johanna Wiedling
- HYDRA Marine Sciences GmbH, Sinzheim, Germany and HYDRA Field Station Elba, Italy
- Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Christian Lott
- HYDRA Marine Sciences GmbH, Sinzheim, Germany and HYDRA Field Station Elba, Italy
| | - Wolfgang Bach
- MARUM–Center for Marine Environmental Research, University of Bremen, Bremen, Germany
| | - Hanna Kuhfuß
- HYDRA Marine Sciences GmbH, Sinzheim, Germany and HYDRA Field Station Elba, Italy
- Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Gunter Wegener
- Max Planck Institute for Marine Microbiology, Bremen, Germany
- MARUM–Center for Marine Environmental Research, University of Bremen, Bremen, Germany
| | - Michael E. Böttcher
- Geochemistry & Isotope Biogeochemistry Group, Leibniz Institute for Baltic Sea Research (IOW), Warnemünde, Germany
| | | | - Anna Lichtschlag
- National Oceanography Centre, University of Southampton Water Front Campus, Southampton, United Kingdom
| | | | - Miriam Weber
- HYDRA Marine Sciences GmbH, Sinzheim, Germany and HYDRA Field Station Elba, Italy
- Max Planck Institute for Marine Microbiology, Bremen, Germany
| |
Collapse
|
12
|
Al-Sadi AM, Kazerooni EA. Illumina-MiSeq analysis of fungi in acid lime roots reveals dominance of Fusarium and variation in fungal taxa. Sci Rep 2018; 8:17388. [PMID: 30478417 PMCID: PMC6255777 DOI: 10.1038/s41598-018-35404-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Accepted: 11/05/2018] [Indexed: 11/08/2022] Open
Abstract
A study was conducted to analyze fungal diversity in the roots of acid lime (Citrus aurantifolia) collected from Oman, a semi-arid country located in the South Eastern part of the Arabian Peninsula. MiSeq analysis showed the Ascomycota and Sordariomycetes were the most abundant phylum and class in acid lime roots, respectively. Glomeromycota, Basidiomycota and Microsporidia were the other fungal phyla, while Glomeromycetes and some other classes belonging to Ascomycota and Basidiomycota were detected at lower frequencies. The genus Fusarium was the most abundant in all samples, making up 46 to 95% of the total reads. Some fungal genera of Arbuscular mycorrhizae and nematophagous fungi were detected in some of the acid lime roots. Analysis of the level of fungal diversity showed that no significant differences exist among groups of root samples (from different locations) in their Chao richness and Shannon diversity levels (P < 0.05). Principle component analysis of fungal communities significantly separated samples according to their locations. This is the first study to evaluate fungal diversity in acid lime roots using high throughput sequencing analysis. The study reveals the presence of various fungal taxa in the roots, dominated by Fusarium species and including some mycorrhizae and nematophagous fungi.
Collapse
Affiliation(s)
- Abdullah M Al-Sadi
- Department of Crop Sciences, College of Agricultural and Marine Sciences, Sultan Qaboos University, Oman, PO Box 34, Alkhoud, 123, Oman.
| | - Elham A Kazerooni
- Department of Crop Sciences, College of Agricultural and Marine Sciences, Sultan Qaboos University, Oman, PO Box 34, Alkhoud, 123, Oman
| |
Collapse
|
13
|
In situ development of a methanotrophic microbiome in deep-sea sediments. ISME JOURNAL 2018; 13:197-213. [PMID: 30154496 PMCID: PMC6298960 DOI: 10.1038/s41396-018-0263-1] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Revised: 07/06/2018] [Accepted: 08/04/2018] [Indexed: 01/11/2023]
Abstract
Emission of the greenhouse gas methane from the seabed is globally controlled by marine aerobic and anaerobic methanotrophs gaining energy via methane oxidation. However, the processes involved in the assembly and dynamics of methanotrophic populations in complex natural microbial communities remain unclear. Here we investigated the development of a methanotrophic microbiome following subsurface mud eruptions at Håkon Mosby mud volcano (1250 m water depth). Freshly erupted muds hosted deep-subsurface communities that were dominated by Bathyarchaeota, Atribacteria and Chloroflexi. Methanotrophy was initially limited to a thin surface layer of Methylococcales populations consuming methane aerobically. With increasing distance to the eruptive center, anaerobic methanotrophic archaea, sulfate-reducing Desulfobacterales and thiotrophic Beggiatoaceae developed, and their respective metabolic capabilities dominated the biogeochemical functions of the community. Microbial richness, evenness, and cell numbers of the entire microbial community increased up to tenfold within a few years downstream of the mud flow from the eruptive center. The increasing diversity was accompanied by an up to fourfold increase in sequence abundance of relevant metabolic genes of the anaerobic methanotrophic and thiotrophic guilds. The communities fundamentally changed in their structure and functions as reflected in the metagenome turnover with distance from the eruptive center, and this was reflected in the biogeochemical zonation across the mud volcano caldera. The observed functional succession provides a framework for the response time and recovery of complex methanotrophic communities after disturbances of the deep-sea bed.
Collapse
|
14
|
Establishing anaerobic hydrocarbon-degrading enrichment cultures of microorganisms under strictly anoxic conditions. Nat Protoc 2018; 13:1310-1330. [DOI: 10.1038/nprot.2018.030] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
15
|
Krukenberg V, Riedel D, Gruber-Vodicka HR, Buttigieg PL, Tegetmeyer HE, Boetius A, Wegener G. Gene expression and ultrastructure of meso- and thermophilic methanotrophic consortia. Environ Microbiol 2018; 20:1651-1666. [PMID: 29468803 PMCID: PMC5947290 DOI: 10.1111/1462-2920.14077] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Revised: 02/15/2018] [Accepted: 02/15/2018] [Indexed: 11/27/2022]
Abstract
The sulfate‐dependent, anaerobic oxidation of methane (AOM) is an important sink for methane in marine environments. It is carried out between anaerobic methanotrophic archaea (ANME) and sulfate‐reducing bacteria (SRB) living in syntrophic partnership. In this study, we compared the genomes, gene expression patterns and ultrastructures of three phylogenetically different microbial consortia found in hydrocarbon‐rich environments under different temperature regimes: ANME‐1a/HotSeep‐1 (60°C), ANME‐1a/Seep‐SRB2 (37°C) and ANME‐2c/Seep‐SRB2 (20°C). All three ANME encode a reverse methanogenesis pathway: ANME‐2c encodes all enzymes, while ANME‐1a lacks the gene for N5,N10‐methylene tetrahydromethanopterin reductase (mer) and encodes a methylenetetrahydrofolate reductase (Met). The bacterial partners contain the genes encoding the canonical dissimilatory sulfate reduction pathway. During AOM, all three consortia types highly expressed genes encoding for the formation of flagella or type IV pili and/or c‐type cytochromes, some predicted to be extracellular. ANME‐2c expressed potentially extracellular cytochromes with up to 32 hemes, whereas ANME‐1a and SRB expressed less complex cytochromes (≤ 8 and ≤ 12 heme respectively). The intercellular space of all consortia showed nanowire‐like structures and heme‐rich areas. These features are proposed to enable interspecies electron exchange, hence suggesting that direct electron transfer is a common mechanism to sulfate‐dependent AOM, and that both partners synthesize molecules to enable it.
Collapse
Affiliation(s)
- Viola Krukenberg
- Max Planck Institute for Marine Microbiology, Bremen, 28359, Germany
| | - Dietmar Riedel
- Max Planck Institute for Biophysical Chemistry, Göttingen, 37077, Germany
| | | | - Pier Luigi Buttigieg
- Alfred Wegener Institute, Helmholtz Center for Polar and Marine Research, Bremerhaven, 27570, Germany
| | - Halina E Tegetmeyer
- Alfred Wegener Institute, Helmholtz Center for Polar and Marine Research, Bremerhaven, 27570, Germany.,Center for Biotechnology, Bielefeld University, Bielefeld, 33615, Germany
| | - Antje Boetius
- Max Planck Institute for Marine Microbiology, Bremen, 28359, Germany.,Alfred Wegener Institute, Helmholtz Center for Polar and Marine Research, Bremerhaven, 27570, Germany.,MARUM, Center for Marine Environmental Sciences, University Bremen, Bremen, 28359, Germany
| | - Gunter Wegener
- Max Planck Institute for Marine Microbiology, Bremen, 28359, Germany.,MARUM, Center for Marine Environmental Sciences, University Bremen, Bremen, 28359, Germany
| |
Collapse
|
16
|
Bhattarai S, Cassarini C, Rene ER, Kümmel S, Esposito G, Lens PNL. Enrichment of ANME-2 dominated anaerobic methanotrophy from cold seep sediment in an external ultrafiltration membrane bioreactor. Eng Life Sci 2018; 18:368-378. [PMID: 32624917 DOI: 10.1002/elsc.201700148] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Revised: 12/20/2017] [Accepted: 02/14/2018] [Indexed: 11/08/2022] Open
Abstract
Anaerobic oxidation of methane (AOM) coupled to sulfate reduction is a microbially mediated unique natural phenomenon with an ecological relevance in the global carbon balance and potential application in biotechnology. This study aimed to enrich an AOM performing microbial community with the main focus on anaerobic methanotrophic archaea (ANME) present in sediments from the Ginsburg mud volcano (Gulf of Cadiz), a known site for AOM, in a membrane bioreactor (MBR) for 726 days at 22 (± 3)°C and at ambient pressure. The MBR was equipped with a cylindrical external ultrafiltration membrane, fed a defined medium containing artificial seawater and operated at a cross flow velocity of 0.02 m/min. Sulfide production with simultaneous sulfate reduction was in equimolar ratio between days 480 and 585 of MBR operation, whereas methane consumption was in oscillating trend. At the end of the MBR operation (day 726), the enriched biomass was incubated with 13C labeled methane, 13C labeled inorganic carbon was produced and the AOM rate based on 13C-inorganic carbon was 1.2 μmol/(gdw d). Microbial analysis of the enriched biomass at 400 and 726 days of MBR operation showed that ANME-2 and Desulfosarcina type sulfate reducing bacteria were enriched in the MBR, which formed closely associated aggregates. The major relevance of this study is the enrichment of an AOM consortium in a MBR system which can assist to explore the ecophysiology of ANME and provides an opportunity to explore the potential application of AOM.
Collapse
Affiliation(s)
| | - Chiara Cassarini
- UNESCO-IHE Institute for Water Education The Netherlands.,Department of Microbiology National University of Ireland Galway Ireland
| | - Eldon R Rene
- UNESCO-IHE Institute for Water Education The Netherlands
| | - Steffen Kümmel
- Department for Isotope Biogeochemistry Helmholtz-Centre for Environmental Research (UFZ) Leipzig Germany
| | - Giovanni Esposito
- Department of Civil and Mechanical Engineering University of Cassino and Southern Lazio Cassino (FR) Italy
| | - Piet N L Lens
- UNESCO-IHE Institute for Water Education The Netherlands.,Department of Microbiology National University of Ireland Galway Ireland
| |
Collapse
|
17
|
Bhattarai S, Cassarini C, Gonzalez-Gil G, Egger M, Slomp CP, Zhang Y, Esposito G, Lens PNL. Anaerobic Methane-Oxidizing Microbial Community in a Coastal Marine Sediment: Anaerobic Methanotrophy Dominated by ANME-3. MICROBIAL ECOLOGY 2017; 74:608-622. [PMID: 28389729 DOI: 10.1007/s00248-017-0978-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2016] [Accepted: 03/28/2017] [Indexed: 06/07/2023]
Abstract
The microbial community inhabiting the shallow sulfate-methane transition zone in coastal sediments from marine Lake Grevelingen (The Netherlands) was characterized, and the ability of the microorganisms to carry out anaerobic oxidation of methane coupled to sulfate reduction was assessed in activity tests. In vitro activity tests of the sediment with methane and sulfate demonstrated sulfide production coupled to the simultaneous consumption of sulfate and methane at approximately equimolar ratios over a period of 150 days. The maximum sulfate reduction rate was 5 μmol sulfate per gram dry weight per day during the incubation period. Diverse archaeal and bacterial clades were retrieved from the sediment with the majority of them clustered with Euryarchaeota, Thaumarcheota, Bacteroidetes, and Proteobacteria. The 16S rRNA gene sequence analysis showed that the sediment from marine Lake Grevelingen contained anaerobic methanotrophic Archaea (ANME) and methanogens as archaeal clades with a role in the methane cycling. ANME at the studied site mainly belong to the ANME-3 clade. This study provides one of the few reports for the presence of ANME-3 in a shallow coastal sediment. Sulfate-reducing bacteria from Desulfobulbus clades were found among the sulfate reducers, however, with very low relative abundance. Desulfobulbus has previously been commonly found associated with ANME, whereas in our study, ANME-3 and Desulfobulbus were not observed simultaneously in clusters, suggesting the possibility of independent AOM by ANME-3.
Collapse
Affiliation(s)
- Susma Bhattarai
- UNESCO-IHE, Westvest-7, P.O. Box 3015, Delft, 2601, DA, The Netherlands.
| | - Chiara Cassarini
- UNESCO-IHE, Westvest-7, P.O. Box 3015, Delft, 2601, DA, The Netherlands
| | | | - Matthias Egger
- Department of Earth Sciences - Geochemistry, Faculty of Geosciences, Utrecht University, P.O. Box 80021, 3508 TA, Utrecht, The Netherlands
- Center for Geomicrobiology, Department of Bioscience, Aarhus University, Ny Munkegade 114, 8000, Aarhus, Denmark
| | - Caroline P Slomp
- Department of Earth Sciences - Geochemistry, Faculty of Geosciences, Utrecht University, P.O. Box 80021, 3508 TA, Utrecht, The Netherlands
| | - Yu Zhang
- State Key Laboratory of Ocean Engineering, Shanghai Jiao Tong University, Dongchuan Rd. 800, Shanghai, 200240, People's Republic of China
| | - Giovanni Esposito
- Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, via Di Biasio 43, 03043, Cassino, FR, Italy
| | - Piet N L Lens
- UNESCO-IHE, Westvest-7, P.O. Box 3015, Delft, 2601, DA, The Netherlands
| |
Collapse
|
18
|
Saad S, Bhatnagar S, Tegetmeyer HE, Geelhoed JS, Strous M, Ruff SE. Transient exposure to oxygen or nitrate reveals ecophysiology of fermentative and sulfate-reducing benthic microbial populations. Environ Microbiol 2017; 19:4866-4881. [PMID: 28836729 PMCID: PMC5763382 DOI: 10.1111/1462-2920.13895] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Revised: 08/07/2017] [Accepted: 08/15/2017] [Indexed: 12/01/2022]
Abstract
For the anaerobic remineralization of organic matter in marine sediments, sulfate reduction coupled to fermentation plays a key role. Here, we enriched sulfate‐reducing/fermentative communities from intertidal sediments under defined conditions in continuous culture. We transiently exposed the cultures to oxygen or nitrate twice daily and investigated the community response. Chemical measurements, provisional genomes and transcriptomic profiles revealed trophic networks of microbial populations. Sulfate reducers coexisted with facultative nitrate reducers or aerobes enabling the community to adjust to nitrate or oxygen pulses. Exposure to oxygen and nitrate impacted the community structure, but did not suppress fermentation or sulfate reduction as community functions, highlighting their stability under dynamic conditions. The most abundant sulfate reducer in all cultures, related to Desulfotignum balticum, appeared to have coupled both acetate‐ and hydrogen oxidation to sulfate reduction. We describe a novel representative of the widespread uncultured candidate phylum Fermentibacteria (formerly candidate division Hyd24‐12). For this strictly anaerobic, obligate fermentative bacterium, we propose the name ‘USabulitectum silens’ and identify it as a partner of sulfate reducers in marine sediments. Overall, we provide insights into the function of fermentative, as well as sulfate‐reducing microbial communities and their adaptation to a dynamic environment.
Collapse
Affiliation(s)
- Sainab Saad
- Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Srijak Bhatnagar
- UC Davis Genome Center, University of California Davis, Davis, CA, USA
| | - Halina E Tegetmeyer
- Max Planck Institute for Marine Microbiology, Bremen, Germany.,Institute for Genome Research and Systems Biology, Center for Biotechnology, University of Bielefeld, Bielefeld, Germany
| | - Jeanine S Geelhoed
- Max Planck Institute for Marine Microbiology, Bremen, Germany.,Department of Ecosystem Studies, NIOZ Royal Netherlands Institute for Sea Research, Yerseke, The Netherlands
| | - Marc Strous
- Max Planck Institute for Marine Microbiology, Bremen, Germany.,Institute for Genome Research and Systems Biology, Center for Biotechnology, University of Bielefeld, Bielefeld, Germany.,Department of Geoscience, University of Calgary, Calgary, AB, Canada
| | - S Emil Ruff
- Max Planck Institute for Marine Microbiology, Bremen, Germany.,Department of Geoscience, University of Calgary, Calgary, AB, Canada
| |
Collapse
|
19
|
Monodeuterated Methane, an Isotopic Tool To Assess Biological Methane Metabolism Rates. mSphere 2017; 2:mSphere00309-17. [PMID: 28861523 PMCID: PMC5566838 DOI: 10.1128/mspheredirect.00309-17] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Accepted: 07/31/2017] [Indexed: 11/20/2022] Open
Abstract
Microbial methane consumption is a critical component of the global carbon cycle, with wide-ranging implications for climate regulation and hydrocarbon exploitation. Nonetheless, quantifying methane metabolism typically involves logistically challenging methods and/or specialized equipment; these impediments have limited our understanding of methane fluxes and reservoirs in natural systems, making effective management difficult. Here, we offer an easily implementable, precise method using monodeuterated methane (CH3D) that advances three specific aims. First, it allows users to directly compare methane consumption rates between different experimental treatments of the same inoculum. Second, by empirically linking the CH3D procedure with the well-established 14C radiocarbon approach, we determine absolute scaling factors that facilitate rate measurements for several aerobic and anaerobic systems of interest. Third, CH3D represents a helpful tool in evaluating the relationship between methane activation and full oxidation in methanotrophic metabolisms. The procedural advantages, consistency, and novel research questions enabled by the CH3D method should prove useful in a wide range of culture-based and environmental microbial systems to further elucidate methane metabolism dynamics. Biological methane oxidation is a globally relevant process that mediates the flux of an important greenhouse gas through both aerobic and anaerobic metabolic pathways. However, measuring these metabolic rates presents many obstacles, from logistical barriers to regulatory hurdles and poor precision. Here we present a new approach for investigating microbial methane metabolism based on hydrogen atom dynamics, which is complementary to carbon-focused assessments of methanotrophy. The method uses monodeuterated methane (CH3D) as a metabolic substrate, quantifying the aqueous D/H ratio over time using off-axis integrated cavity output spectroscopy. This approach represents a nontoxic, comparatively rapid, and straightforward approach that supplements existing radiotopic and stable carbon isotopic methods; by probing hydrogen atoms, it offers an additional dimension for examining rates and pathways of methane metabolism. We provide direct comparisons between the CH3D procedure and the well-established 14CH4 radiotracer method for several methanotrophic systems, including type I and II aerobic methanotroph cultures and methane-seep sediment slurries and carbonate rocks under anoxic and oxic incubation conditions. In all applications tested, methane consumption values calculated via the CH3D method were directly and consistently proportional to 14C radiolabel-derived methane oxidation rates. We also employed this method in a nontraditional experimental setup, using flexible, gas-impermeable bags to investigate the role of pressure on seep sediment methane oxidation rates. Results revealed an 80% increase over atmospheric pressure in methanotrophic rates the equivalent of ~900-m water depth, highlighting the importance of this parameter on methane metabolism and exhibiting the flexibility of the newly described method. IMPORTANCE Microbial methane consumption is a critical component of the global carbon cycle, with wide-ranging implications for climate regulation and hydrocarbon exploitation. Nonetheless, quantifying methane metabolism typically involves logistically challenging methods and/or specialized equipment; these impediments have limited our understanding of methane fluxes and reservoirs in natural systems, making effective management difficult. Here, we offer an easily implementable, precise method using monodeuterated methane (CH3D) that advances three specific aims. First, it allows users to directly compare methane consumption rates between different experimental treatments of the same inoculum. Second, by empirically linking the CH3D procedure with the well-established 14C radiocarbon approach, we determine absolute scaling factors that facilitate rate measurements for several aerobic and anaerobic systems of interest. Third, CH3D represents a helpful tool in evaluating the relationship between methane activation and full oxidation in methanotrophic metabolisms. The procedural advantages, consistency, and novel research questions enabled by the CH3D method should prove useful in a wide range of culture-based and environmental microbial systems to further elucidate methane metabolism dynamics.
Collapse
|
20
|
Al-Bulushi IM, Bani-Uraba MS, Guizani NS, Al-Khusaibi MK, Al-Sadi AM. Illumina MiSeq sequencing analysis of fungal diversity in stored dates. BMC Microbiol 2017; 17:72. [PMID: 28347268 PMCID: PMC5369213 DOI: 10.1186/s12866-017-0985-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Accepted: 03/17/2017] [Indexed: 12/05/2022] Open
Abstract
Background Date palm has been a major fruit tree in the Middle East over thousands of years, especially in the Arabian Peninsula. Dates are consumed fresh (Rutab) or after partial drying and storage (Tamar) during off-season. The aim of the study was to provide in-depth analysis of fungal communities associated with the skin (outer part) and mesocarp (inner fleshy part) of stored dates (Tamar) of two cultivars (Khenizi and Burny) through the use of Illumina MiSeq sequencing. Results The study revealed the dominance of Ascomycota (94%) in both cultivars, followed by Chytridiomycota (4%) and Zygomycota (2%). Among the classes recovered, Eurotiomycetes, Dothideomycetes, Saccharomycetes and Sordariomycetes were the most dominant. A total of 54 fungal species were detected, with species belonging to Penicillium, Alternaria, Cladosporium and Aspergillus comprising more than 60% of the fungal reads. Some potentially mycotoxin-producing fungi were detected in stored dates, including Aspergillus flavus, A. versicolor and Penicillium citrinum, but their relative abundance was very limited (<0.5%). PerMANOVA analysis revealed the presence of insignificant differences in fungal communities between date parts or date cultivars, indicating that fungal species associated with the skin may also be detected in the mesocarp. It also indicates the possible contamination of dates from different cultivars with similar fungal species, even though if they are obtained from different areas. Conclusion The analysis shows the presence of different fungal species in dates. This appears to be the first study to report 25 new fungal species in Oman and 28 new fungal species from date fruits. The study discusses the sources of fungi on dates and the presence of potentially mycotoxin producing fungi on date skin and mesocarp.
Collapse
Affiliation(s)
- Ismail M Al-Bulushi
- Department of Food Science and Nutrition, College of Agricultural and Marine Sciences, Sultan Qaboos University, P.O. Box-34, Al-Khod, 123, Oman
| | - Muna S Bani-Uraba
- Department of Food Science and Nutrition, College of Agricultural and Marine Sciences, Sultan Qaboos University, P.O. Box-34, Al-Khod, 123, Oman
| | - Nejib S Guizani
- Department of Food Science and Nutrition, College of Agricultural and Marine Sciences, Sultan Qaboos University, P.O. Box-34, Al-Khod, 123, Oman
| | - Mohammed K Al-Khusaibi
- Department of Food Science and Nutrition, College of Agricultural and Marine Sciences, Sultan Qaboos University, P.O. Box-34, Al-Khod, 123, Oman
| | - Abdullah M Al-Sadi
- Department of Crop Sciences, College of Agricultural and Marine Sciences, Sultan Qaboos University, P.O. Box-34, Al-Khod, 123, Oman.
| |
Collapse
|