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Steinsdóttir HGR, Gómez Ramírez E, Mhatre S, Schauberger C, Bertagnolli AD, Pratte ZA, Stewart FJ, Thamdrup B, Bristow LA. Anaerobic methane oxidation in a coastal oxygen minimum zone: spatial and temporal dynamics. Environ Microbiol 2022; 24:2361-2379. [PMID: 35415879 PMCID: PMC9323439 DOI: 10.1111/1462-2920.16003] [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: 10/19/2021] [Revised: 04/05/2022] [Accepted: 04/05/2022] [Indexed: 11/28/2022]
Abstract
Coastal waters are a major source of marine methane to the atmosphere. Particularly high concentrations of this potent greenhouse gas are found in anoxic waters, but it remains unclear if and to what extent anaerobic methanotrophs mitigate the methane flux. Here we investigate the long-term dynamics in methanotrophic activity and the methanotroph community in the coastal oxygen minimum zone (OMZ) of Golfo Dulce, Costa Rica, combining biogeochemical analyses, experimental incubations, and 16S rRNA gene sequencing over three consecutive years. Our results demonstrate a stable redox zonation across the years with high concentrations of methane (up to 1.7 μmol L-1 ) in anoxic bottom waters. However, we also measured high activities of anaerobic methane oxidation in the OMZ core (rate constant, k, averaging 30 yr-1 in 2018 and 8 yr-1 in 2019-2020). The OPU3 and Deep Sea-1 clades of the Methylococcales were implicated as conveyors of the activity, peaking in relative abundance 5-25 m below the oxic-anoxic interface and in the deep anoxic water, respectively. Although their genetic capacity for anaerobic methane oxidation remains unexplored, their sustained high relative abundance indicates an adaptation of these clades to the anoxic, methane-rich OMZ environment, allowing them to play major roles in mitigating methane fluxes. This article is protected by copyright. All rights reserved.
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Affiliation(s)
| | - Eddy Gómez Ramírez
- CIMAR, Universidad de Costa Rica, San Pedro de Montes de Oca, Costa Rica
| | - Snehit Mhatre
- Department of Biology, University of Southern Denmark, Odense, Denmark
| | | | - Anthony D Bertagnolli
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, Montana
| | - Zoe A Pratte
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, Montana
| | - Frank J Stewart
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, Montana.,School of Biological Sciences, Center for Microbial Dynamics and Infection, Georgia Institute of Technology, Atlanta, GA
| | - Bo Thamdrup
- Department of Biology, University of Southern Denmark, Odense, Denmark
| | - Laura A Bristow
- Department of Biology, University of Southern Denmark, Odense, Denmark
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2
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Pavlovska M, Prekrasna I, Dykyi E, Zotov A, Dzhulai A, Frolova A, Slobodnik J, Stoica E. Niche partitioning of bacterial communities along the stratified water column in the Black Sea. Microbiologyopen 2021; 10:e1195. [PMID: 34180601 PMCID: PMC8217838 DOI: 10.1002/mbo3.1195] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 04/21/2021] [Accepted: 04/21/2021] [Indexed: 11/22/2022] Open
Abstract
The Black Sea is the largest semi‐closed permanently anoxic basin on our planet with long‐term stratification. The study aimed at describing the Black Sea microbial community taxonomic and functional composition within the range of depths spanning across oxic/anoxic interface, and to uncover the factors behind both their vertical and regional differentiation. 16S rRNA gene MiSeq sequencing was applied to get the data on microbial community taxonomy, and the PICRUSt pipeline was used to infer their functional profile. The normoxic zone was mainly inhabited by primary producers and heterotrophic prokaryotes (e.g., Flavobacteriaceae, Rhodobacteraceae, Synechococcaceae) whereas the euxinic zone—by heterotrophic and chemoautotrophic taxa (e.g., MSBL2, Piscirickettsiaceae, and Desulfarculaceae). Assimilatory sulfate reduction and oxygenic photosynthesis were prevailing within the normoxic zone, while the role of nitrification, dissimilatory sulfate reduction, and anoxygenic photosynthesis increased in the oxygen‐depleted water column part. Regional differentiation of microbial communities between the Ukrainian shelf and offshore zone was detected as well, yet it was significantly less pronounced than the vertical one. It is suggested that regional differentiation within a well‐oxygenated zone is driven by the difference in phytoplankton communities providing various substrates for the prokaryotes, whereas redox stratification is the main driving force behind microbial community vertical structure.
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Affiliation(s)
- Mariia Pavlovska
- State Institution National Antarctic Scientific Center, Kyiv, Ukraine.,Ukrainian Scientific Center of Ecology of the Sea, Odesa, Ukraine.,National University of Life and Environmental Sciences of Ukraine, Kyiv, Ukraine
| | | | - Evgen Dykyi
- State Institution National Antarctic Scientific Center, Kyiv, Ukraine.,Ukrainian Scientific Center of Ecology of the Sea, Odesa, Ukraine
| | - Andrii Zotov
- State Institution National Antarctic Scientific Center, Kyiv, Ukraine.,State Institution Institute of Marine Biology of the NAS of Ukraine, Odesa, Ukraine
| | - Artem Dzhulai
- State Institution National Antarctic Scientific Center, Kyiv, Ukraine
| | - Alina Frolova
- Institute of Molecular Biology and Genetics of NASU, Kyiv, Ukraine
| | | | - Elena Stoica
- National Institute for Marine Research and Development "Grigore Antipa", Constanta, Romania
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3
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van Vliet DM, von Meijenfeldt FB, Dutilh BE, Villanueva L, Sinninghe Damsté JS, Stams AJ, Sánchez‐Andrea I. The bacterial sulfur cycle in expanding dysoxic and euxinic marine waters. Environ Microbiol 2021; 23:2834-2857. [PMID: 33000514 PMCID: PMC8359478 DOI: 10.1111/1462-2920.15265] [Citation(s) in RCA: 111] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 09/03/2020] [Accepted: 09/28/2020] [Indexed: 01/29/2023]
Abstract
Dysoxic marine waters (DMW, < 1 μM oxygen) are currently expanding in volume in the oceans, which has biogeochemical, ecological and societal consequences on a global scale. In these environments, distinct bacteria drive an active sulfur cycle, which has only recently been recognized for open-ocean DMW. This review summarizes the current knowledge on these sulfur-cycling bacteria. Critical bottlenecks and questions for future research are specifically addressed. Sulfate-reducing bacteria (SRB) are core members of DMW. However, their roles are not entirely clear, and they remain largely uncultured. We found support for their remarkable diversity and taxonomic novelty by mining metagenome-assembled genomes from the Black Sea as model ecosystem. We highlight recent insights into the metabolism of key sulfur-oxidizing SUP05 and Sulfurimonas bacteria, and discuss the probable involvement of uncultivated SAR324 and BS-GSO2 bacteria in sulfur oxidation. Uncultivated Marinimicrobia bacteria with a presumed organoheterotrophic metabolism are abundant in DMW. Like SRB, they may use specific molybdoenzymes to conserve energy from the oxidation, reduction or disproportionation of sulfur cycle intermediates such as S0 and thiosulfate, produced from the oxidation of sulfide. We expect that tailored sampling methods and a renewed focus on cultivation will yield deeper insight into sulfur-cycling bacteria in DMW.
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Affiliation(s)
- Daan M. van Vliet
- Laboratory of MicrobiologyWageningen University and Research, Stippeneng 4, 6708WEWageningenNetherlands
| | | | - Bas E. Dutilh
- Theoretical Biology and Bioinformatics, Science for LifeUtrecht University, Padualaan 8, 3584 CHUtrechtNetherlands
| | - Laura Villanueva
- Department of Marine Microbiology and BiogeochemistryRoyal Netherlands Institute for Sea Research (NIOZ), Utrecht University, Landsdiep 4, 1797 SZ, 'tHorntje (Texel)Netherlands
| | - Jaap S. Sinninghe Damsté
- Department of Marine Microbiology and BiogeochemistryRoyal Netherlands Institute for Sea Research (NIOZ), Utrecht University, Landsdiep 4, 1797 SZ, 'tHorntje (Texel)Netherlands
- Department of Earth Sciences, Faculty of GeosciencesUtrecht University, Princetonlaan 8A, 3584 CBUtrechtNetherlands
| | - Alfons J.M. Stams
- Laboratory of MicrobiologyWageningen University and Research, Stippeneng 4, 6708WEWageningenNetherlands
- Centre of Biological EngineeringUniversity of Minho, Campus de Gualtar, 4710‐057BragaPortugal
| | - Irene Sánchez‐Andrea
- Laboratory of MicrobiologyWageningen University and Research, Stippeneng 4, 6708WEWageningenNetherlands
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4
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Fuchsman CA, Stüeken EE. Using modern low-oxygen marine ecosystems to understand the nitrogen cycle of the Paleo- and Mesoproterozoic oceans. Environ Microbiol 2020; 23:2801-2822. [PMID: 32869502 DOI: 10.1111/1462-2920.15220] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 08/25/2020] [Accepted: 08/27/2020] [Indexed: 11/29/2022]
Abstract
During the productive Paleoproterozoic (2.4-1.8 Ga) and less productive Mesoproterozoic (1.8-1.0 Ga), the ocean was suboxic to anoxic and multicellular organisms had not yet evolved. Here, we link geologic information about the Proterozoic ocean to microbial processes in modern low-oxygen systems. High iron concentrations and rates of Fe cycling in the Proterozoic are the largest differences from modern oxygen-deficient zones. In anoxic waters, which composed most of the Paleoproterozoic and ~40% of the Mesoproterozoic ocean, nitrogen cycling dominated. Rates of N2 production by denitrification and anammox were likely linked to sinking organic matter fluxes and in situ primary productivity under anoxic conditions. Additionally autotrophic denitrifiers could have used reduced iron or methane. 50% of the Mesoproterozoic ocean may have been suboxic, promoting nitrification and metal oxidation in the suboxic water and N2 O and N2 production by partial and complete denitrification in anoxic zones in organic aggregates. Sulfidic conditions may have composed ~10% of the Mesoproterozoic ocean focused along continental margins. Due to low nitrate concentrations in offshore regions, anammox bacteria likely dominated N2 production immediately above sulfidic zones, but in coastal regions, higher nitrate concentrations probably promoted complete S-oxidizing autotrophic denitrification at the sulfide interface.
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Affiliation(s)
- Clara A Fuchsman
- Horn Point Laboratory, University of Maryland Center for Environmental Science, Cambridge, MD, 21613, USA
| | - Eva E Stüeken
- School of Earth & Environmental Sciences, University of St Andrews, St Andrews, KY16 9AL, Scotland, UK
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5
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Suter EA, Pachiadaki MG, Montes E, Edgcomb VP, Scranton MI, Taylor CD, Taylor GT. Diverse nitrogen cycling pathways across a marine oxygen gradient indicate nitrogen loss coupled to chemoautotrophic activity. Environ Microbiol 2020; 23:2747-2764. [PMID: 32761757 DOI: 10.1111/1462-2920.15187] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2019] [Revised: 08/01/2020] [Accepted: 08/02/2020] [Indexed: 11/28/2022]
Abstract
Genetic markers and geochemical assays of microbial nitrogen cycling processes, including autotrophic and heterotrophic denitrification, anammox, ammonia oxidation, and nitrite oxidation, were examined across the oxycline, suboxic, and anoxic zones of the Cariaco Basin, Venezuela. Ammonia and nitrite oxidation genes were expressed through the entire gradient. Transcripts associated with autotrophic and heterotrophic denitrifiers were mostly confined to the suboxic zone and below but were also present in particles in the oxycline. Anammox genes and transcripts were detected over a narrow depth range near the bottom of the suboxic zone and coincided with secondary NO2 - maxima and available NH4 + . Dissolved inorganic nitrogen (DIN) amendment incubations and comparisons between our sampling campaigns suggested that denitrifier activity may be closely coupled with NO3 - availability. Expression of denitrification genes at depths of high rates of chemoautotrophic carbon fixation and phylogenetic analyses of nitrogen cycling genes and transcripts indicated a diverse array of denitrifiers, including chemoautotrophs capable of using NO3 - to oxidize reduced sulfur species. Thus, results suggest that the Cariaco Basin nitrogen cycle is influenced by autotrophic carbon cycling in addition to organic matter oxidation and anammox.
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Affiliation(s)
- Elizabeth A Suter
- School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY, USA.,Biology, Chemistry, and Environmental Studies Department, Center for Environmental Research and Coastal Oceans Monitoring, Molloy College, Rockville Centre, NY, USA.,Department of Biological Sciences, Wagner College, Staten Island, NY, USA
| | - Maria G Pachiadaki
- Woods Hole Oceanographic Institution, Woods Hole, MA, USA.,Bigelow Laboratory for Ocean Sciences, East Boothbay, ME, USA
| | - Enrique Montes
- College of Marine Science, University of South Florida, St. Petersburg, FL, USA
| | | | - Mary I Scranton
- School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY, USA
| | - Craig D Taylor
- Woods Hole Oceanographic Institution, Woods Hole, MA, USA
| | - Gordon T Taylor
- School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY, USA
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6
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He P, Xie L, Zhang X, Li J, Lin X, Pu X, Yuan C, Tian Z, Li J. Microbial Diversity and Metabolic Potential in the Stratified Sansha Yongle Blue Hole in the South China Sea. Sci Rep 2020; 10:5949. [PMID: 32249806 PMCID: PMC7136235 DOI: 10.1038/s41598-020-62411-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 03/11/2020] [Indexed: 01/08/2023] Open
Abstract
The Sansha Yongle Blue Hole is the world’s deepest (301 m) underwater cave and has a sharp redox gradient, with oligotrophic, anoxic, and sulfidic bottom seawater. In order to discover the microbial communities and their special biogeochemical pathways in the blue hole, we analyzed the 16S ribosomal RNA amplicons and metagenomes of microbials from seawater depths with prominent physical, chemical, and biological features. Redundancy analysis showed that dissolved oxygen was the most important factor affecting the microbial assemblages of the blue hole and surrounding open sea waters, and significantly explained 44.7% of the total variation, followed by silicate, temperature, sulfide, ammonium, methane, nitrous oxide, nitrate, dissolved organic carbon, salinity, particulate organic carbon, and chlorophyll a. We identified a bloom of Alteromonas (34.9%) at the primary nitrite maximum occurring in close proximity to the chlorophyll a peak in the blue hole. Genomic potential for nitrate reduction of Alteromonas might contribute to this maximum under oxygen decrease. Genes that would allow for aerobic ammonium oxidation, complete denitrification, and sulfur-oxidization were enriched at nitrate/nitrite-sulfide transition zone (90 and 100 m) of the blue hole, but not anammox pathways. Moreover, γ-Proteobacterial clade SUP05, ε-Proteobacterial genera Sulfurimonas and Arcobacter, and Chlorobi harbored genes for sulfur-driven denitrification process that mediated nitrogen loss and sulfide removal. In the anoxic bottom seawater (100-300 m), high levels of sulfate reducers and dissimilatory sulfite reductase gene (dsrA) potentially created a sulfidic zone of ~200 m thickness. Our findings suggest that in the oligotrophic Sansha Yongle Blue Hole, O2 deficiency promotes nitrogen- and sulfur-cycling processes mediated by metabolically versatile microbials.
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Affiliation(s)
- Peiqing He
- Key Laboratory of Science and Technology for Marine Ecology and Environment, First Institute of Oceanography, Ministry of Natural Resources, 6 Xianxialing Road, Qingdao, 266061, China. .,Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266071, China. .,Key Laboratory of Natural Products of Qingdao, Qingdao, 266061, China.
| | - Linping Xie
- Key Laboratory of Science and Technology for Marine Ecology and Environment, First Institute of Oceanography, Ministry of Natural Resources, 6 Xianxialing Road, Qingdao, 266061, China.,Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266071, China
| | - Xuelei Zhang
- Key Laboratory of Science and Technology for Marine Ecology and Environment, First Institute of Oceanography, Ministry of Natural Resources, 6 Xianxialing Road, Qingdao, 266061, China.,Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266071, China
| | - Jiang Li
- Key Laboratory of Science and Technology for Marine Ecology and Environment, First Institute of Oceanography, Ministry of Natural Resources, 6 Xianxialing Road, Qingdao, 266061, China.,Key Laboratory of Natural Products of Qingdao, Qingdao, 266061, China
| | - Xuezheng Lin
- Key Laboratory of Science and Technology for Marine Ecology and Environment, First Institute of Oceanography, Ministry of Natural Resources, 6 Xianxialing Road, Qingdao, 266061, China.,Key Laboratory of Natural Products of Qingdao, Qingdao, 266061, China
| | - Xinming Pu
- Key Laboratory of Science and Technology for Marine Ecology and Environment, First Institute of Oceanography, Ministry of Natural Resources, 6 Xianxialing Road, Qingdao, 266061, China.,Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266071, China
| | - Chao Yuan
- Key Laboratory of Science and Technology for Marine Ecology and Environment, First Institute of Oceanography, Ministry of Natural Resources, 6 Xianxialing Road, Qingdao, 266061, China.,Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266071, China
| | - Ziwen Tian
- Research Center for Islands and Coastal Zone, First Institute of Oceanography, Ministry of Natural Resources, 6 Xianxialing Road, Qingdao, 266061, China
| | - Jie Li
- Marine Engineering Environment and Geomatic Center, First Institute of Oceanography, Ministry of Natural Resources, 6 Xianxialing Road, Qingdao, 266061, China
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7
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Lahme S, Callbeck CM, Eland LE, Wipat A, Enning D, Head IM, Hubert CR. Comparison of sulfide‐oxidizing
Sulfurimonas
strains reveals a new mode of thiosulfate formation in subsurface environments. Environ Microbiol 2020; 22:1784-1800. [DOI: 10.1111/1462-2920.14894] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 12/02/2019] [Accepted: 12/11/2019] [Indexed: 01/18/2023]
Affiliation(s)
- Sven Lahme
- School of Natural and Environmental SciencesNewcastle University Devonshire Building (3rd floor) Newcastle upon Tyne NE1 7RU UK
| | | | - Lucy E. Eland
- School of ComputingNewcastle University Newcastle upon Tyne UK
| | - Anil Wipat
- School of ComputingNewcastle University Newcastle upon Tyne UK
| | - Dennis Enning
- ExxonMobil Upstream Research Company Spring Texas USA
| | - Ian M. Head
- School of Natural and Environmental SciencesNewcastle University Devonshire Building (3rd floor) Newcastle upon Tyne NE1 7RU UK
| | - Casey R.J. Hubert
- School of Natural and Environmental SciencesNewcastle University Devonshire Building (3rd floor) Newcastle upon Tyne NE1 7RU UK
- Department of Biological SciencesUniversity of Calgary Calgary Canada
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8
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Arcobacter peruensis sp. nov., a Chemolithoheterotroph Isolated from Sulfide- and Organic-Rich Coastal Waters off Peru. Appl Environ Microbiol 2019; 85:AEM.01344-19. [PMID: 31585991 DOI: 10.1128/aem.01344-19] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 09/05/2019] [Indexed: 02/06/2023] Open
Abstract
Members of the epsilonproteobacterial genus Arcobacter have been identified to be potentially important sulfide oxidizers in marine coastal, seep, and stratified basin environments. In the highly productive upwelling waters off the coast of Peru, Arcobacter cells comprised 3 to 25% of the total microbial community at a near-shore station where sulfide concentrations exceeded 20 μM in bottom waters. From the chemocline where the Arcobacter population exceeded 106 cells ml-1 and where high rates of denitrification (up to 6.5 ± 0.4 μM N day-1) and dark carbon fixation (2.8 ± 0.2 μM C day-1) were measured, we isolated a previously uncultivated Arcobacter species, Arcobacter peruensis sp. nov. (BCCM LMG-31510). Genomic analysis showed that A. peruensis possesses genes encoding sulfide oxidation and denitrification pathways but lacks the ability to fix CO2 via autotrophic carbon fixation pathways. Genes encoding transporters for organic carbon compounds, however, were present in the A. peruensis genome. Physiological experiments demonstrated that A. peruensis grew best on a mix of sulfide, nitrate, and acetate. Isotope labeling experiments further verified that A. peruensis completely reduced nitrate to N2 and assimilated acetate but did not fix CO2, thus coupling heterotrophic growth to sulfide oxidation and denitrification. Single-cell nanoscale secondary ion mass spectrometry analysis of samples taken from shipboard isotope labeling experiments also confirmed that the Arcobacter population in situ did not substantially fix CO2 The efficient growth yield associated with the chemolithoheterotrophic metabolism of A. peruensis may allow this Arcobacter species to rapidly bloom in eutrophic and sulfide-rich waters off the coast of Peru.IMPORTANCE Our multidisciplinary approach provides new insights into the ecophysiology of a newly isolated environmental Arcobacter species, as well as the physiological flexibility within the Arcobacter genus and sulfide-oxidizing, denitrifying microbial communities within oceanic oxygen minimum zones (OMZs). The chemolithoheterotrophic species Arcobacter peruensis may play a substantial role in the diverse consortium of bacteria that is capable of coupling denitrification and fixed nitrogen loss to sulfide oxidation in eutrophic, sulfidic coastal waters. With increasing anthropogenic pressures on coastal regions, e.g., eutrophication and deoxygenation (D. Breitburg, L. A. Levin, A. Oschlies, M. Grégoire, et al., Science 359:eaam7240, 2018, https://doi.org/10.1126/science.aam7240), niches where sulfide-oxidizing, denitrifying heterotrophs such as A. peruensis thrive are likely to expand.
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9
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Suter EA, Pachiadaki M, Taylor GT, Astor Y, Edgcomb VP. Free‐living chemoautotrophic and particle‐attached heterotrophic prokaryotes dominate microbial assemblages along a pelagic redox gradient. Environ Microbiol 2017; 20:693-712. [DOI: 10.1111/1462-2920.13997] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Revised: 11/09/2017] [Accepted: 11/13/2017] [Indexed: 01/28/2023]
Affiliation(s)
- Elizabeth A. Suter
- School of Marine and Atmospheric SciencesStony Brook UniversityStony Brook NY USA
- Department of Biological SciencesWagner CollegeStaten Island NY 10301 USA
| | - Maria Pachiadaki
- Woods Hole Oceanographic InstitutionWoods Hole MA USA
- Bigelow Laboratory for Ocean SciencesEast Boothbay ME USA
| | - Gordon T. Taylor
- School of Marine and Atmospheric SciencesStony Brook UniversityStony Brook NY USA
| | - Yrene Astor
- Fundación La Salle de Ciencias Naturales, EDIMARPorlamar Nueva Esparta Venezuela
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10
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Laas P, Šatova E, Lips I, Lips U, Simm J, Kisand V, Metsis M. Near-Bottom Hypoxia Impacts Dynamics of Bacterioplankton Assemblage throughout Water Column of the Gulf of Finland (Baltic Sea). PLoS One 2016; 11:e0156147. [PMID: 27213812 PMCID: PMC4877108 DOI: 10.1371/journal.pone.0156147] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Accepted: 05/10/2016] [Indexed: 11/19/2022] Open
Abstract
Over the past century the spread of hypoxia in the Baltic Sea has been drastic, reaching its ‘arm’ into the easternmost sub-basin, the Gulf of Finland. The hydrographic and climatological properties of the gulf offer a broad suite of discrete niches for microbial communities. The current study explores spatiotemporal dynamics of bacterioplankton community in the Gulf of Finland using massively parallel sequencing of 16S rRNA fragments obtained by amplifying community DNA from spring to autumn period. The presence of redoxcline and drastic seasonal changes make spatiotemporal dynamics of bacterioplankton community composition (BCC) and abundances in such estuary remarkably complex. To the best of our knowledge, this is the first study that analyses spatiotemporal dynamics of BCC in relation to phytoplankton bloom throughout the water column (and redoxcline), not only at the surface layer. We conclude that capability to survive (or benefit from) shifts between oxic and hypoxic conditions is vital adaptation for bacteria to thrive in such environments. Our results contribute to the understanding of emerging patterns in BCCs that occupy hydrographically similar estuaries dispersed all over the world, and we suggest the presence of a global redox- and salinity-driven metacommunity. These results have important implications for understanding long-term ecological and biogeochemical impacts of hypoxia expansion in the Baltic Sea (and similar ecosystems), as well as global biogeography of bacteria specialized inhabiting similar ecosystems.
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Affiliation(s)
- Peeter Laas
- Marine Systems Institute at Tallinn University of Technology, Akadeemia Rd. 15A, 12618, Tallinn, Estonia
- * E-mail:
| | - Elina Šatova
- Department of Gene Technology, Tallinn University of Technology, Akadeemia tee 15, 12618, Tallinn, Estonia
| | - Inga Lips
- Marine Systems Institute at Tallinn University of Technology, Akadeemia Rd. 15A, 12618, Tallinn, Estonia
| | - Urmas Lips
- Marine Systems Institute at Tallinn University of Technology, Akadeemia Rd. 15A, 12618, Tallinn, Estonia
| | - Jaak Simm
- Department of Gene Technology, Tallinn University of Technology, Akadeemia tee 15, 12618, Tallinn, Estonia
| | - Veljo Kisand
- Institute of Technology at University of Tartu, Nooruse 1, 50411, Tartu, Estonia
| | - Madis Metsis
- Institute of Mathematics and Natural Sciences, Tallinn University, Narva Rd. 25, 10120, Tallinn, Estonia
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11
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Coupled RNA-SIP and metatranscriptomics of active chemolithoautotrophic communities at a deep-sea hydrothermal vent. ISME JOURNAL 2016; 10:1925-38. [PMID: 26872039 PMCID: PMC5029171 DOI: 10.1038/ismej.2015.258] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Revised: 12/07/2015] [Accepted: 12/10/2015] [Indexed: 01/13/2023]
Abstract
The chemolithoautotrophic microbial community of the rocky subseafloor potentially provides a large amount of organic carbon to the deep ocean, yet our understanding of the activity and metabolic complexity of subseafloor organisms remains poorly described. A combination of metagenomic, metatranscriptomic, and RNA stable isotope probing (RNA-SIP) analyses were used to identify the metabolic potential, expression patterns, and active autotrophic bacteria and archaea and their pathways present in low-temperature hydrothermal fluids from Axial Seamount, an active submarine volcano. Metagenomic and metatranscriptomic results showed the presence of genes and transcripts for sulfur, hydrogen, and ammonium oxidation, oxygen respiration, denitrification, and methanogenesis, as well as multiple carbon fixation pathways. In RNA-SIP experiments across a range of temperatures under reducing conditions, the enriched 13C fractions showed differences in taxonomic and functional diversity. At 30 °C and 55 °C, Epsilonproteobacteria were dominant, oxidizing hydrogen and primarily reducing nitrate. Methanogenic archaea were also present at 55 °C, and were the only autotrophs present at 80 °C. Correspondingly, the predominant CO2 fixation pathways changed from the reductive tricarboxylic acid (rTCA) cycle to the reductive acetyl-CoA pathway with increasing temperature. By coupling RNA-SIP with meta-omics, this study demonstrates the presence and activity of distinct chemolithoautotrophic communities across a thermal gradient of a deep-sea hydrothermal vent.
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12
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Noguerola I, Picazo A, Llirós M, Camacho A, Borrego CM. Diversity of freshwaterEpsilonproteobacteriaand dark inorganic carbon fixation in the sulphidic redoxcline of a meromictic karstic lake. FEMS Microbiol Ecol 2015. [PMID: 26195601 DOI: 10.1093/femsec/fiv086] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Imma Noguerola
- Group of Molecular Microbial Ecology, Institute of Aquatic Ecology, Universitat de Girona, Campus de Montilivi, E-17071 Girona, Spain
| | - Antonio Picazo
- Cavanilles Institute for Biodiversity and Evolutionary Biology and Department of Microbiology and Ecology, Edificio de Investigación 'Jeroni Muñoz', Campus de Burjassot, Universitat de Valencia, E-46100, Burjassot, Valencia, Spain
| | - Marc Llirós
- Université Catholique de Louvain, Institut des Sciences de la Vie, Place Croix du Sud, 4/5 L07.07.06, B-1348 Louvain-La-Neuve, Belgium
| | - Antonio Camacho
- Cavanilles Institute for Biodiversity and Evolutionary Biology and Department of Microbiology and Ecology, Edificio de Investigación 'Jeroni Muñoz', Campus de Burjassot, Universitat de Valencia, E-46100, Burjassot, Valencia, Spain
| | - Carles M Borrego
- Group of Molecular Microbial Ecology, Institute of Aquatic Ecology, Universitat de Girona, Campus de Montilivi, E-17071 Girona, Spain Water Quality and Microbial Diversity, Catalan Institute for Water Research (ICRA), H2O Building, Scientific and Technological Park of the University of Girona, Emili Grahit 101, E-17003 Girona, Spain
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Laas P, Simm J, Lips I, Lips U, Kisand V, Metsis M. Redox-specialized bacterioplankton metacommunity in a temperate estuary. PLoS One 2015; 10:e0122304. [PMID: 25860812 PMCID: PMC4393233 DOI: 10.1371/journal.pone.0122304] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Accepted: 02/19/2015] [Indexed: 11/30/2022] Open
Abstract
This study explored the spatiotemporal dynamics of the bacterioplankton community composition in the Gulf of Finland (easternmost sub-basin of the Baltic Sea) based on phylogenetic analysis of 16S rDNA sequences acquired from community samples via pyrosequencing. Investigations of bacterioplankton in hydrographically complex systems provide good insight into the strategies by which microbes deal with spatiotemporal hydrographic gradients, as demonstrated by our research. Many ribotypes were closely affiliated with sequences isolated from environments with similar steep physiochemical gradients and/or seasonal changes, including seasonally anoxic estuaries. Hence, one of the main conclusions of this study is that marine ecosystems where oxygen and salinity gradients co-occur can be considered a habitat for a cosmopolitan metacommunity consisting of specialized groups occupying niches universal to such environments throughout the world. These niches revolve around functional capabilities to utilize different electron receptors and donors (including trace metal and single carbon compounds). On the other hand, temporal shifts in the bacterioplankton community composition at the surface layer were mainly connected to the seasonal succession of phytoplankton and the inflow of freshwater species. We also conclude that many relatively abundant populations are indigenous and well-established in the area.
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Affiliation(s)
- Peeter Laas
- Marine Systems Institute at Tallinn University of Technology, Tallinn, Estonia
- * E-mail:
| | - Jaak Simm
- Department of Electrical Engineering (ESAT), STADIUS Center for Dynamical Systems, Signal Processing, and Data Analytics, KU Leuven, Leuven, Belgium
- iMinds Medical IT, Leuven, Belgium
- Department of Gene Technology, Tallinn University of Technology, Tallinn, Estonia
| | - Inga Lips
- Marine Systems Institute at Tallinn University of Technology, Tallinn, Estonia
| | - Urmas Lips
- Marine Systems Institute at Tallinn University of Technology, Tallinn, Estonia
| | - Veljo Kisand
- Institute of Technology at University of Tartu, Tartu, Estonia
| | - Madis Metsis
- Institute of Mathematics and Natural Sciences, Tallinn University, Tallinn, Estonia
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Wang Y, Zhang WP, Cao HL, Shek CS, Tian RM, Wong YH, Batang Z, Al-Suwailem A, Qian PY. Diversity and distribution of eukaryotic microbes in and around a brine pool adjacent to the Thuwal cold seeps in the Red Sea. Front Microbiol 2014; 5:37. [PMID: 24575081 PMCID: PMC3922051 DOI: 10.3389/fmicb.2014.00037] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Accepted: 01/20/2014] [Indexed: 11/25/2022] Open
Abstract
A hypoxic/suboxic brine pool at a depth of about 850 m was discovered near the Thuwal cold seeps in the Red Sea. Filled with high concentrations of hydrogen sulfide and ammonia, such a brine pool might limit the spread of eukaryotic organisms. Here, we compared the communities of the eukaryotic microbes in a microbial mat, sediments and water samples distributed in 7 sites within and adjacent to the brine pool. Taxonomic classification of the pyrosequenced 18S rRNA amplicon reads showed that fungi highly similar to the species identified along the Arabic coast were almost ubiquitous in the water and sediment samples, supporting their wide distribution in various environments. The microbial mat displayed the highest species diversity and contained grazers and a considerable percentage of unclassified species. Phylogeny-based methods revealed novel lineages representing a majority of the reads from the interface between the sea water and brine pool. Phylogenetic relationships with more reference sequences suggest that the lineages were affiliated with novel Alveolata and Euglenozoa inhabiting the interface where chemosynthetic prokaryotes are highly proliferative due to the strong chemocline and halocline. The brine sediments harbored abundant species highly similar to invertebrate gregarine parasites identified in different oxygen-depleted sediments. Therefore, the present findings support the uniqueness of some microbial eukaryotic groups in this cold seep brine system.
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Affiliation(s)
- Yong Wang
- Division of Life Science, Hong Kong University of Science and Technology Hong Kong, China ; Sanya Institute of Deep Sea Science and Engineering, Chinese Academy of Sciences San Ya, China
| | - Wei Peng Zhang
- Division of Life Science, Hong Kong University of Science and Technology Hong Kong, China
| | - Hui Luo Cao
- Division of Life Science, Hong Kong University of Science and Technology Hong Kong, China
| | - Chun Shum Shek
- Division of Life Science, Hong Kong University of Science and Technology Hong Kong, China
| | - Ren Mao Tian
- Division of Life Science, Hong Kong University of Science and Technology Hong Kong, China
| | - Yue Him Wong
- Division of Life Science, Hong Kong University of Science and Technology Hong Kong, China
| | - Zenon Batang
- Coastal and Marine Resources Core Laboratory, King Abdullah University of Science and Technology Jeddah, Saudi Arabia
| | - Abdulaziz Al-Suwailem
- Coastal and Marine Resources Core Laboratory, King Abdullah University of Science and Technology Jeddah, Saudi Arabia
| | - Pei-Yuan Qian
- Division of Life Science, Hong Kong University of Science and Technology Hong Kong, China
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Glaubitz S, Abraham WR, Jost G, Labrenz M, Jürgens K. Pyruvate utilization by a chemolithoautotrophic epsilonproteobacterial key player of pelagic Baltic Sea redoxclines. FEMS Microbiol Ecol 2013; 87:770-9. [PMID: 24279499 DOI: 10.1111/1574-6941.12263] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2013] [Revised: 11/14/2013] [Accepted: 11/20/2013] [Indexed: 11/27/2022] Open
Abstract
Pelagic redoxclines of the central Baltic Sea are dominated by the epsilonproteobacterial group Sulfurimonas GD17, considered to be the major driver of chemolithoautotrophic denitrification in this habitat. Autecological investigations of a recently isolated representative of this environmental group, Sulfurimonas gotlandica str. GD1(T), demonstrated that the bacterium grows best under sulfur-oxidizing, denitrifying conditions. However, in the presence of bicarbonate, this strain is able to use pyruvate as both an additional carbon source and an alternative electron donor. These observations suggested that the environmental group GD17 actively metabolizes organic substrates in situ. To examine this possibility, we used RNA-based stable isotope probing (RNA-SIP) on a natural redoxcline community provided with ¹³C-labeled pyruvate. While in this experiment, we were able to identify putative heterotrophic microorganisms, the uptake of ¹³C-pyruvate in GD17 nucleic acids could not be established. To resolve these contradictory findings, combined incorporation experiments with ¹⁴C- and ¹³C-labeled pyruvate were carried out in cells of strain GD1(T) cultivated under chemolithoautotrophic conditions, which favor pyruvate uptake rather than oxidation. An analysis of the labeled biomolecules revealed that pyruvate was mostly incorporated in cellular components such as amino acids, whose synthesis requires only minimal transformation. Carbon transfer into nucleic acids was not observed, explaining the inability of RNA-SIP to detect pyruvate incorporation by strain GD1(T) and the environmental group GD17. Together, these findings suggest that by integrating organic compounds such as pyruvate into cellular components S. gotlandica GD1(T) is able to replenish chemolithoautotrophic growth and thus ensure its survival in nutrient-limited habitats such as marine pelagic redoxclines.
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Affiliation(s)
- Sabine Glaubitz
- Section Biological Oceanography, Leibniz-Institute for Baltic Sea Research Warnemuende (IOW), Rostock, Germany
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Schunck H, Lavik G, Desai DK, Großkopf T, Kalvelage T, Löscher CR, Paulmier A, Contreras S, Siegel H, Holtappels M, Rosenstiel P, Schilhabel MB, Graco M, Schmitz RA, Kuypers MMM, LaRoche J. Giant hydrogen sulfide plume in the oxygen minimum zone off Peru supports chemolithoautotrophy. PLoS One 2013; 8:e68661. [PMID: 23990875 PMCID: PMC3749208 DOI: 10.1371/journal.pone.0068661] [Citation(s) in RCA: 130] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2012] [Accepted: 06/01/2013] [Indexed: 11/30/2022] Open
Abstract
In Eastern Boundary Upwelling Systems nutrient-rich waters are transported to the ocean surface, fuelling high photoautotrophic primary production. Subsequent heterotrophic decomposition of the produced biomass increases the oxygen-depletion at intermediate water depths, which can result in the formation of oxygen minimum zones (OMZ). OMZs can sporadically accumulate hydrogen sulfide (H2S), which is toxic to most multicellular organisms and has been implicated in massive fish kills. During a cruise to the OMZ off Peru in January 2009 we found a sulfidic plume in continental shelf waters, covering an area >5500 km2, which contained ∼2.2×104 tons of H2S. This was the first time that H2S was measured in the Peruvian OMZ and with ∼440 km3 the largest plume ever reported for oceanic waters. We assessed the phylogenetic and functional diversity of the inhabiting microbial community by high-throughput sequencing of DNA and RNA, while its metabolic activity was determined with rate measurements of carbon fixation and nitrogen transformation processes. The waters were dominated by several distinct γ-, δ- and ε-proteobacterial taxa associated with either sulfur oxidation or sulfate reduction. Our results suggest that these chemolithoautotrophic bacteria utilized several oxidants (oxygen, nitrate, nitrite, nitric oxide and nitrous oxide) to detoxify the sulfidic waters well below the oxic surface. The chemolithoautotrophic activity at our sampling site led to high rates of dark carbon fixation. Assuming that these chemolithoautotrophic rates were maintained throughout the sulfidic waters, they could be representing as much as ∼30% of the photoautotrophic carbon fixation. Postulated changes such as eutrophication and global warming, which lead to an expansion and intensification of OMZs, might also increase the frequency of sulfidic waters. We suggest that the chemolithoautotrophically fixed carbon may be involved in a negative feedback loop that could fuel further sulfate reduction and potentially stabilize the sulfidic OMZ waters.
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Affiliation(s)
- Harald Schunck
- Research Division Marine Biogeochemistry, GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, Germany
- Institute for General Microbiology, Christian-Albrechts-University, Kiel, Germany
| | - Gaute Lavik
- Department of Biogeochemistry, Max-Planck-Institute for Marine Microbiology, Bremen, Germany
| | - Dhwani K. Desai
- Research Division Marine Biogeochemistry, GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, Germany
- Department of Biology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Tobias Großkopf
- Research Division Marine Biogeochemistry, GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, Germany
- College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter, United Kingdom
| | - Tim Kalvelage
- Department of Biogeochemistry, Max-Planck-Institute for Marine Microbiology, Bremen, Germany
| | - Carolin R. Löscher
- Institute for General Microbiology, Christian-Albrechts-University, Kiel, Germany
| | - Aurélien Paulmier
- Department of Biogeochemistry, Max-Planck-Institute for Marine Microbiology, Bremen, Germany
- Laboratory for Studies in Geophysics and Spatial Oceanography, Institute of Research for Development, Toulouse, France
- Dirección de Investigaciones Oceanográficas, Instituto del Mar del Perú, Callao, Peru
| | - Sergio Contreras
- Department of Biogeochemistry, Max-Planck-Institute for Marine Microbiology, Bremen, Germany
- Large Lakes Observatory, University of Minnesota Duluth, Duluth, Minnesota, United States of America
| | - Herbert Siegel
- Physical Oceanography and Instrumentation, Leibniz Institute for Baltic Sea Research Warnemünde, Rostock, Germany
| | - Moritz Holtappels
- Department of Biogeochemistry, Max-Planck-Institute for Marine Microbiology, Bremen, Germany
| | - Philip Rosenstiel
- Institute of Clinical Molecular Biology, Christian-Albrechts-University, Kiel, Germany
| | - Markus B. Schilhabel
- Institute of Clinical Molecular Biology, Christian-Albrechts-University, Kiel, Germany
| | - Michelle Graco
- Dirección de Investigaciones Oceanográficas, Instituto del Mar del Perú, Callao, Peru
| | - Ruth A. Schmitz
- Institute for General Microbiology, Christian-Albrechts-University, Kiel, Germany
| | - Marcel M. M. Kuypers
- Department of Biogeochemistry, Max-Planck-Institute for Marine Microbiology, Bremen, Germany
| | - Julie LaRoche
- Research Division Marine Biogeochemistry, GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, Germany
- Department of Biology, Dalhousie University, Halifax, Nova Scotia, Canada
- * E-mail:
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17
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Labrenz M, Grote J, Mammitzsch K, Boschker HTS, Laue M, Jost G, Glaubitz S, Jürgens K. Sulfurimonas gotlandica sp. nov., a chemoautotrophic and psychrotolerant epsilonproteobacterium isolated from a pelagic redoxcline, and an emended description of the genus Sulfurimonas. Int J Syst Evol Microbiol 2013; 63:4141-4148. [PMID: 23749282 PMCID: PMC3836495 DOI: 10.1099/ijs.0.048827-0] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
A psychro- and aerotolerant bacterium was isolated from the sulfidic water of a pelagic redox zone of the central Baltic Sea. The slightly curved rod- or spiral-shaped cells were motile by one polar flagellum or two bipolar flagella. Growth was chemolithoautotrophic, with nitrate or nitrite as electron acceptor and either a variety of sulfur species of different oxidation states or hydrogen as electron donor. Although the bacterium was able to utilize organic substances such as acetate, pyruvate, peptone and yeast extract for growth, these compounds yielded considerably lower cell numbers than obtained with reduced sulfur or hydrogen; in addition, bicarbonate supplementation was necessary. The cells also had an absolute requirement for NaCl. Optimal growth occurred at 15 °C and at pH 6.6–8.0. The predominant fatty acid of this organism was 16 : 1ω7c, with 3-OH 14 : 0, 16 : 0, 16 : 1ω5c+t and 18 : 1ω7c present in smaller amounts. The DNA G+C content was 33.6 mol%. As determined in 16S rRNA gene sequence phylogeny analysis, the isolate belongs to the genus Sulfurimonas, within the class Epsilonproteobacteria, with 93.7 to 94.2 % similarity to the other species of the genus Sulfurimonas, Sulfurimonas autotrophica, Sulfurimonas paralvinellae and Sulfurimonas denitrificans. However, the distinct physiological and genotypic differences from these previously described taxa support the description of a novel species, Sulfurimonas gotlandica sp. nov. The type strain is GD1T ( = DSM 19862T = JCM 16533T). Our results also justify an emended description of the genus Sulfurimonas.
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Affiliation(s)
- Matthias Labrenz
- IOW Leibniz Institute for Baltic Sea Research Warnemuende (IOW), Germany
| | - Jana Grote
- IOW Leibniz Institute for Baltic Sea Research Warnemuende (IOW), Germany
| | - Kerstin Mammitzsch
- IOW Leibniz Institute for Baltic Sea Research Warnemuende (IOW), Germany
| | | | - Michael Laue
- Arbeitsbereich Medizinische Biologie und Elektronenmikroskopisches Zentrum (EMZ), Universität Rostock, Germany
| | - Günter Jost
- IOW Leibniz Institute for Baltic Sea Research Warnemuende (IOW), Germany
| | - Sabine Glaubitz
- IOW Leibniz Institute for Baltic Sea Research Warnemuende (IOW), Germany
| | - Klaus Jürgens
- IOW Leibniz Institute for Baltic Sea Research Warnemuende (IOW), Germany
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SUP05 dominates the Gammaproteobacterial sulfur oxidizer assemblages in pelagic redoxclines of the central Baltic and Black Seas. Appl Environ Microbiol 2013; 79:2767-76. [PMID: 23417000 DOI: 10.1128/aem.03777-12] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Gammaproteobacterial sulfur oxidizers (GSOs), particularly SUP05-related sequences, have been found worldwide in numerous oxygen-deficient marine environments. However, knowledge regarding their abundance, distribution, and ecological role is scarce. In this study, on the basis of phylogenetic analyses of 16S rRNA gene sequences originating from a Baltic Sea pelagic redoxcline, the in situ abundances of different GSO subgroups were quantified by CARD-FISH (catalyzed reporter fluorescence in situ hybridization) with oligonucleotide probes developed specifically for this purpose. Additionally, ribulose bisphosphate carboxylase/oxygenase form II (cbbM) gene transcript clone libraries were used to detect potential active chemolithoautotrophic GSOs in the Baltic Sea. Taken together, the results obtained by these two approaches demonstrated the existence of two major phylogenetic subclusters embedded within the GSO, one of them affiliated with sequences of the previously described SUP05 subgroup. CARD-FISH analyses revealed that only SUP05 occurred in relatively high numbers, reaching 10 to 30% of the total prokaryotes around the oxic-anoxic interface, where oxygen and sulfide concentrations are minimal. The applicability of the oligonucleotide probes was confirmed with samples from the Black Sea redoxcline, in which the SUP05 subgroup accounted for 10 to 13% of the total prokaryotic abundance. The cbbM transcripts presumably originating from SUP05 cells support previous evidence for the chemolithoautotrophic activity of this phylogenetic group. Our findings on the vertical distribution and high abundance of SUP05 suggest that this group plays an important role in marine redoxcline biogeochemistry, probably as anaerobic or aerobic sulfur oxidizers.
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Anderson R, Wylezich C, Glaubitz S, Labrenz M, Jürgens K. Impact of protist grazing on a key bacterial group for biogeochemical cycling in Baltic Sea pelagic oxic/anoxic interfaces. Environ Microbiol 2013; 15:1580-94. [PMID: 23368413 DOI: 10.1111/1462-2920.12078] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2012] [Revised: 12/17/2012] [Accepted: 12/20/2012] [Indexed: 11/27/2022]
Abstract
Barrier zones between oxic and anoxic water masses (redoxclines) host highly active prokaryotic communities with important roles in biogeochemical cycling. In Baltic Sea pelagic redoxclines, Epsilonproteobacteria of the genus Sulfurimonas (subgroup GD17) have been shown to dominate chemoautotrophic denitrification. However, little is known on the loss processes affecting this prokaryotic group. In the present study, the protist grazing impact on the Sulfurimonas subgroup GD17 was determined for suboxic and oxygen/hydrogen sulphide interface depths of Baltic Sea redoxclines, using predator exclusion assays and bacterial amendment with the cultured representative 'Sulfurimonas gotlandica' strain GD1. Additionally, the principal bacterivores were identified by RNA-Stable Isotope Probing (RNA-SIP). The natural Sulfurimonas subgroup GD17 population grew strongly under oxygen/hydrogen sulphide interface conditions (doubling time: 1-1.5 days), but protist grazing could consume the complete new cell production per day. In suboxic samples, little or no growth of Sulfurimonas subgroup GD17 was observed. RNA-SIP identified five active grazers, belonging to typical redoxcline ciliates (Oligohymenophorea, Prostomatea) and globally widespread marine flagellate groups (MAST-4, Chrysophyta, Cercozoa). Overall, we demonstrate for the first time that protist grazing can control the growth, and potentially the vertical distribution, of a chemolithoautotrophic key-player of oxic/anoxic interfaces.
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Affiliation(s)
- Ruth Anderson
- Department of Biological Oceanography, Leibniz Institute for Baltic Sea Research, Seestrasse 15, 18119, Rostock-Warnemünde, Germany.
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20
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DeLorenzo S, Bräuer SL, Edgmont CA, Herfort L, Tebo BM, Zuber P. Ubiquitous dissolved inorganic carbon assimilation by marine bacteria in the Pacific Northwest coastal ocean as determined by stable isotope probing. PLoS One 2012; 7:e46695. [PMID: 23056406 PMCID: PMC3463544 DOI: 10.1371/journal.pone.0046695] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2012] [Accepted: 09/06/2012] [Indexed: 11/25/2022] Open
Abstract
In order to identify bacteria that assimilate dissolved inorganic carbon (DIC) in the northeast Pacific Ocean, stable isotope probing (SIP) experiments were conducted on water collected from 3 different sites off the Oregon and Washington coasts in May 2010, and one site off the Oregon Coast in September 2008 and March 2009. Samples were incubated in the dark with 2 mM (13)C-NaHCO(3), doubling the average concentration of DIC typically found in the ocean. Our results revealed a surprising diversity of marine bacteria actively assimilating DIC in the dark within the Pacific Northwest coastal waters, indicating that DIC fixation is relevant for the metabolism of different marine bacterial lineages, including putatively heterotrophic taxa. Furthermore, dark DIC-assimilating assemblages were widespread among diverse bacterial classes. Alphaproteobacteria, Gammaproteobacteria, and Bacteroidetes dominated the active DIC-assimilating communities across the samples. Actinobacteria, Betaproteobacteria, Deltaproteobacteria, Planctomycetes, and Verrucomicrobia were also implicated in DIC assimilation. Alteromonadales and Oceanospirillales contributed significantly to the DIC-assimilating Gammaproteobacteria within May 2010 clone libraries. 16S rRNA gene sequences related to the sulfur-oxidizing symbionts Arctic96BD-19 were observed in all active DIC assimilating clone libraries. Among the Alphaproteobacteria, clones related to the ubiquitous SAR11 clade were found actively assimilating DIC in all samples. Although not a dominant contributor to our active clone libraries, Betaproteobacteria, when identified, were predominantly comprised of Burkholderia. DIC-assimilating bacteria among Deltaproteobacteria included members of the SAR324 cluster. Our research suggests that DIC assimilation is ubiquitous among many bacterial groups in the coastal waters of the Pacific Northwest marine environment and may represent a significant metabolic process.
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Affiliation(s)
- Suzanne DeLorenzo
- Center for Coastal Margin Observation & Prediction and Division of Environmental & Biomolecular Systems, Oregon Health & Science University, Beaverton, Oregon, United States of America.
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21
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Kirkpatrick JB, Fuchsman CA, Yakushev E, Staley JT, Murray JW. Concurrent activity of anammox and denitrifying bacteria in the Black Sea. Front Microbiol 2012; 3:256. [PMID: 22833740 PMCID: PMC3400275 DOI: 10.3389/fmicb.2012.00256] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Accepted: 06/29/2012] [Indexed: 11/13/2022] Open
Abstract
After the discovery of ANaerobic AMMonium OXidation (anammox) in the environment, the role of heterotrophic denitrification as the main marine pathway for fixed N loss has been questioned. A 3 part, 15 month time series investigating nitrite reductase (nirS) mRNA transcripts at a single location in the Black Sea was conducted in order to better understand the activity of anammox and denitrifying bacteria. Here we show that both of these groups were active, as well as being concurrent in the lower suboxic zone over this time span. Their distributions, however, differed in that only expression of denitrification-type nirS was seen in the upper suboxic zone, where geochemistry was variable. Depth profiles covering the suboxic zone showed that the four groups of anammox-type sequences were expressed consistently in the lower suboxic zone, and were consistent with anammox 16 S rDNA gene profiles. By contrast, denitrifier-type nirS sequence groups were mixed; some groups exhibited consistent expression in the lower suboxic zone, while others appeared less consistent. Co-occurrence of both anammox and denitrifier expression was common and ongoing. Both types of transcripts were also found in samples with low concentrations of sulfide (>2 μM). Six major groups of denitrifier-type nirS transcripts were identified, and several groups of denitrifier-type nirS transcripts were closely related to sequences from the Baltic Sea. An increase in denitrifier-type nirS transcript diversity and depth range in October 2007 corresponded to a small increase in mixed layer net community productivity (NCP) as measured by O(2)/Ar gas ratios, as well as to an increase in N(2) concentrations in the suboxic zone. Taken together, the variations in expression patterns between anammox and denitrification provide one possible explanation as to how near instantaneous rate measurements, such as isotope spike experiments, may regularly detect anammox activity but underreport denitrification.
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Affiliation(s)
- John B. Kirkpatrick
- School of Oceanography, University of Washington, SeattleWA, USA
- Graduate School of Oceanography and Center for Dark Energy Biosphere Investigations, University of Rhode Island, NarragansettRI, USA
| | | | | | - James T. Staley
- Department of Microbiology, University of Washington, SeattleWA, USA
| | - James W. Murray
- School of Oceanography, University of Washington, SeattleWA, USA
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Fuchsman CA, Murray JW, Staley JT. Stimulation of autotrophic denitrification by intrusions of the bosporus plume into the anoxic black sea. Front Microbiol 2012; 3:257. [PMID: 22826706 PMCID: PMC3399223 DOI: 10.3389/fmicb.2012.00257] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2012] [Accepted: 06/30/2012] [Indexed: 12/03/2022] Open
Abstract
Autotrophic denitrification was measured in the southwestern coastal Black Sea, where the Bosporus Plume injects oxidized chemical species (especially O2 and NO3−) into the oxic, suboxic, and anoxic layers. Prominent oxygen intrusions caused an overlap of NOx− and sulfide at the same station where autotrophic denitrification activity was detected with incubation experiments. Several bacteria that have been proposed to oxidize sulfide in other low oxygen environments were found in the Black Sea including SUP05, Sulfurimonas, Arcobacter, and BS-GSO2. Comparison of TRFLP profiles from this mixing zone station and the Western Gyre (a station not affected by the Bosporus Plume) indicate the greatest relative abundance of Sulfurimonas and Arcobacter at the appropriate depths at the mixing zone station. The autotrophic gammaproteobacterium BS-GSO2 correlated with ammonium fluxes rather than with sulfide fluxes and the maximum in SUP05 peak height was shallower than the depths where autotrophic denitrification was detected. Notably, anammox activity was not detected at the mixing zone station, though low levels of DNA from the anammox bacteria CandidatusScalindua were present. These results provide evidence for a modified ecosystem with different N2 production pathways in the southwest coastal region compared to that found in the rest of the Black Sea. Moreover, the same Sulfurimonas phylotype (BS139) was previously detected on >30 μm particles in the suboxic zone of the Western Gyre along with DNA of potential sulfate reducers, so it is possible that particle-attached autotrophic denitrification may be an overlooked N2 production pathway in the central Black Sea as well.
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Affiliation(s)
- Clara A Fuchsman
- School of Oceanography, University of Washington Seattle, WA, USA
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Dissimilatory sulfur cycling in oxygen minimum zones: an emerging metagenomics perspective. Biochem Soc Trans 2012; 39:1859-63. [PMID: 22103540 DOI: 10.1042/bst20110708] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Biological diversity in marine OMZs (oxygen minimum zones) is dominated by a complex community of bacteria and archaea whose anaerobic metabolisms mediate key steps in global nitrogen and carbon cycles. Molecular and physiological studies now confirm that OMZs also support diverse micro-organisms capable of utilizing inorganic sulfur compounds for energy metabolism. The present review focuses specifically on recent metagenomic data that have helped to identify the molecular basis for autotrophic sulfur oxidation with nitrate in the OMZ water column, as well as a cryptic role for heterotrophic sulfate reduction. Interpreted alongside marker gene surveys and process rate measurements, these data suggest an active sulfur cycle with potentially substantial roles in organic carbon input and mineralization and critical links to the OMZ nitrogen cycle. Furthermore, these studies have created a framework for comparing the genomic diversity and ecology of pelagic sulfur-metabolizing communities from diverse low-oxygen regions.
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Distinct and diverse anaerobic bacterial communities in boreal lakes dominated by candidate division OD1. ISME JOURNAL 2012; 6:1640-52. [PMID: 22418623 DOI: 10.1038/ismej.2012.21] [Citation(s) in RCA: 110] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Lakes have a central role in the carbon cycle of the boreal landscape. These systems typically stratify in summer and their hypolimnetic microbial communities influence burial of biogenic organic matter in sediments. The composition of bacterial communities in these suboxic habitats was studied by pyrosequencing of 16S rRNA amplicons from five lakes with variable dissolved organic carbon (DOC) concentrations. Bacterioplankton communities in the hypolimnetic waters were clearly different from the surface layer with candidate division OD1, Chlorobi and Bacteroidetes as dominant community members. Several operational taxonomic units (OTUs) affiliated with candidate division OD1 were abundant and consistently present in the suboxic hypolimnion in these boreal lakes. The overall representation of this group was positively correlated with DOC and methane concentrations. Network analysis of time-series data revealed contrasting temporal patterns but suggested similar ecological roles among the abundant OTUs affiliated with candidate division OD1. Together, stable isotope data and taxonomic classification point to methane oxidation and autotrophic denitrification as important processes in the suboxic zone of boreal lakes. Our data revealed that while hypolimnetic bacterial communities are less dynamic, they appear to be more diverse than communities from the oxic surface layer. An appreciable proportion of the hypolimnetic bacteria belong to poorly described phyla.
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Fuchsman CA, Staley JT, Oakley BB, Kirkpatrick JB, Murray JW. Free-living and aggregate-associated Planctomycetes in the Black Sea. FEMS Microbiol Ecol 2012; 80:402-16. [DOI: 10.1111/j.1574-6941.2012.01306.x] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2011] [Revised: 01/04/2012] [Accepted: 01/05/2012] [Indexed: 11/29/2022] Open
Affiliation(s)
| | - James T. Staley
- Department of Microbiology; University of Washington; Seattle; WA; USA
| | - Brian B. Oakley
- Department of Microbiology; University of Washington; Seattle; WA; USA
| | | | - James W. Murray
- School of Oceanography; University of Washington; Seattle; WA; USA
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Wylezich C, Jürgens K. Protist diversity in suboxic and sulfidic waters of the Black Sea. Environ Microbiol 2011; 13:2939-56. [DOI: 10.1111/j.1462-2920.2011.02569.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Dang H, Chen R, Wang L, Shao S, Dai L, Ye Y, Guo L, Huang G, Klotz MG. Molecular characterization of putative biocorroding microbiota with a novel niche detection of Epsilon- and Zetaproteobacteria in Pacific Ocean coastal seawaters. Environ Microbiol 2011; 13:3059-74. [DOI: 10.1111/j.1462-2920.2011.02583.x] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Fuchsman CA, Kirkpatrick JB, Brazelton WJ, Murray JW, Staley JT. Metabolic strategies of free-living and aggregate-associated bacterial communities inferred from biologic and chemical profiles in the Black Sea suboxic zone. FEMS Microbiol Ecol 2011; 78:586-603. [PMID: 22066565 DOI: 10.1111/j.1574-6941.2011.01189.x] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2010] [Revised: 07/08/2011] [Accepted: 08/14/2011] [Indexed: 11/26/2022] Open
Abstract
The Black Sea is a permanently anoxic basin with a well-defined redox gradient. We combine environmental 16S rRNA gene data from clone libraries, terminal restriction fragment length polymorphisms, and V6 hypervariable region pyrosequences to provide the most detailed bacterial survey to date. Furthermore, this data set is informed by comprehensive geochemical data; using this combination of information, we put forward testable hypotheses regarding possible metabolisms of uncultured bacteria from the Black Sea's suboxic zone (microaerophily, nitrate reduction, manganese cycling, and oxidation of methane, ammonium, and sulfide). Dominant bacteria in the upper suboxic zone included members of the SAR11, SAR324, and Microthrix groups and in the deep suboxic zone included members of BS-GSO-2, Marine Group A, and SUP05. A particulate fraction (30 μm filter) was used to distinguish between free-living and aggregate-attached communities in the suboxic zone. The particulate fraction contained greater diversity of V6 tag sequences than the bulk water samples. Lentisphaera, Epsilonproteobacteria, WS3, Planctomycetes, and Deltaproteobacteria were enriched in the particulate fraction, whereas SAR11 relatives dominated the free-living fraction. On the basis of the bacterial assemblages and simple modeling, we find that in suboxic waters, the interior of sinking aggregates potentially support manganese reduction, sulfate reduction, and sulfur oxidation.
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Affiliation(s)
- Clara A Fuchsman
- School of Oceanography, University of Washington, Seattle, WA, USA.
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Roalkvam I, Jørgensen SL, Chen Y, Stokke R, Dahle H, Hocking WP, Lanzén A, Haflidason H, Steen IH. New insight into stratification of anaerobic methanotrophs in cold seep sediments. FEMS Microbiol Ecol 2011; 78:233-43. [PMID: 21676010 DOI: 10.1111/j.1574-6941.2011.01153.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Methane seepages typically harbor communities of anaerobic methane oxidizers (ANME); however, knowledge about fine-scale vertical variation of ANME in response to geochemical gradients is limited. We investigated microbial communities in sediments below a white microbial mat in the G11 pockmark at Nyegga by 16S rRNA gene tag pyrosequencing and real-time quantitative PCR. A vertical stratification of dominating ANME communities was observed at 4 cmbsf (cm below seafloor) and below in the following order: ANME-2a/b, ANME-1 and ANME-2c. The ANME-1 community was most numerous and comprised single or chains of cells with typical rectangular morphology, accounting up to 89.2% of the retrieved 16S rRNA gene sequences. Detection rates for sulfate-reducing Deltaproteobacteria possibly involved in anaerobic oxidation of methane were low throughout the core. However, a correlation in the abundance of Candidate division JS-1 with ANME-2 was observed, indicating involvement in metabolisms occurring in ANME-2-dominated horizons. The white microbial mat and shallow sediments were dominated by organisms affiliated with Sulfurovum (Epsilonproteobacteria) and Methylococcales (Gammaproteobacteria), suggesting that aerobic oxidation of sulfur and methane is taking place. In intermediate horizons, typical microbial groups associated with methane seeps were recovered. The data are discussed with respect to co-occurring microbial assemblages and interspecies interactions.
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Affiliation(s)
- Irene Roalkvam
- Department of Biology, Centre for Geobiology, University of Bergen, Norway
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Cultivation-independent detection of autotrophic hydrogen-oxidizing bacteria by DNA stable-isotope probing. Appl Environ Microbiol 2011; 77:4931-8. [PMID: 21622787 DOI: 10.1128/aem.00285-11] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Knallgas bacteria are a physiologically defined group that is primarily studied using cultivation-dependent techniques. Given that current cultivation techniques fail to grow most bacteria, cultivation-independent techniques that selectively detect and identify knallgas bacteria will improve our ability to study their diversity and distribution. We used stable-isotope probing (SIP) to identify knallgas bacteria in rhizosphere soil of legumes and in a microbial mat from Obsidian Pool in Yellowstone National Park. When samples were incubated in the dark, incorporation of (13)CO(2) was H(2) dependent. SIP enabled the detection of knallgas bacteria that were not detected by cultivation, and the majority of bacteria identified in the rhizosphere soils were betaproteobacteria predominantly related to genera previously known to oxidize hydrogen. Bacteria in soil grew on hydrogen at concentrations as low as 100 ppm. A hydB homolog encoding a putative high-affinity NiFe hydrogenase was amplified from (13)C-labeled DNA from both vetch and clover rhizosphere soil. The results indicate that knallgas bacteria can be detected by SIP and populations that respond to different H(2) concentrations can be distinguished. The methods described here should be applicable to a variety of ecosystems and will enable the discovery of additional knallgas bacteria that are resistant to cultivation.
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Llirós M, Alonso-Sáez L, Gich F, Plasencia A, Auguet O, Casamayor EO, Borrego CM. Active bacteria and archaea cells fixing bicarbonate in the dark along the water column of a stratified eutrophic lagoon. FEMS Microbiol Ecol 2011; 77:370-84. [DOI: 10.1111/j.1574-6941.2011.01117.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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La Cono V, Smedile F, Bortoluzzi G, Arcadi E, Maimone G, Messina E, Borghini M, Oliveri E, Mazzola S, L'Haridon S, Toffin L, Genovese L, Ferrer M, Giuliano L, Golyshin PN, Yakimov MM. Unveiling microbial life in new deep-sea hypersaline Lake Thetis. Part I: Prokaryotes and environmental settings. Environ Microbiol 2011; 13:2250-68. [PMID: 21518212 DOI: 10.1111/j.1462-2920.2011.02478.x] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In September 2008, an expedition of the RV Urania was devoted to exploration of the genomic richness of deep hypersaline anoxic lakes (DHALs) located in the Western part of the Mediterranean Ridge. Approximately 40 nautical miles SE from Urania Lake, the presence of anoxic hypersaline lake, which we named Thetis, was confirmed by swath bathymetry profiling and through immediate sampling casts. The brine surface of the Thetis Lake is located at a depth of 3258 m with a thickness of ≈ 157 m. Brine composition was found to be thalassohaline, saturated by NaCl with a total salinity of 348‰, which is one of highest value reported for DHALs. Similarly to other Mediterranean DHALs, seawater-brine interface of Thetis represents a steep pycno- and chemocline with gradients of salinity, electron donors and acceptors and posseses a remarkable stratification of prokaryotic communities, observed to be more metabolically active in the upper interface where redox gradient was sharper. [(14) C]-bicarbonate fixation analysis revealed that microbial communities are sustained by sulfur-oxidizing chemolithoautotrophic primary producers that thrive within upper interface. Besides microaerophilic autotrophy, heterotrophic sulfate reduction, methanogenesis and anaerobic methane oxidation are likely the predominant processes driving the ecosystem of Thetis Lake.
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Affiliation(s)
- Violetta La Cono
- Institute for Coastal Marine Environment, CNR, Spianata S.Raineri 86, 98122 Messina, Italy
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