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Algavi YM, Borenstein E. Relative dispersion ratios following fecal microbiota transplant elucidate principles governing microbial migration dynamics. Nat Commun 2024; 15:4447. [PMID: 38789466 PMCID: PMC11126695 DOI: 10.1038/s41467-024-48717-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Accepted: 05/08/2024] [Indexed: 05/26/2024] Open
Abstract
Microorganisms frequently migrate from one ecosystem to another. Yet, despite the potential importance of this process in modulating the environment and the microbial ecosystem, our understanding of the fundamental forces that govern microbial dispersion is still lacking. Moreover, while theoretical models and in-vitro experiments have highlighted the contribution of species interactions to community assembly, identifying such interactions in vivo, specifically in communities as complex as the human gut, remains challenging. To address this gap, here we introduce a robust and rigorous computational framework, termed Relative Dispersion Ratio (RDR) analysis, and leverage data from well-characterized fecal microbiota transplant trials, to rigorously pinpoint dependencies between taxa during the colonization of human gastrointestinal tract. Our analysis identifies numerous pairwise dependencies between co-colonizing microbes during migration between gastrointestinal environments. We further demonstrate that identified dependencies agree with previously reported findings from in-vitro experiments and population-wide distribution patterns. Finally, we explore metabolic dependencies between these taxa and characterize the functional properties that facilitate effective dispersion. Collectively, our findings provide insights into the principles and determinants of community dynamics following ecological translocation, informing potential opportunities for precise community design.
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Affiliation(s)
- Yadid M Algavi
- Faculty of Medical & Health Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Elhanan Borenstein
- Faculty of Medical & Health Sciences, Tel Aviv University, Tel Aviv, Israel.
- The Blavatnik School of Computer Science, Tel Aviv University, Tel Aviv, Israel.
- Santa Fe Institute, Santa Fe, NM, USA.
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2
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Chowdhury A, Ventura GT, Owino Y, Lalk EJ, MacAdam N, Dooma JM, Ono S, Fowler M, MacDonald A, Bennett R, MacRae RA, Hubert CRJ, Bentley JN, Kerr MJ. Cold seep formation from salt diapir-controlled deep biosphere oases. Proc Natl Acad Sci U S A 2024; 121:e2316878121. [PMID: 38466851 PMCID: PMC10963010 DOI: 10.1073/pnas.2316878121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Accepted: 01/24/2024] [Indexed: 03/13/2024] Open
Abstract
Deep sea cold seeps are sites where hydrogen sulfide, methane, and other hydrocarbon-rich fluids vent from the ocean floor. They are an important component of Earth's carbon cycle in which subsurface hydrocarbons form the energy source for highly diverse benthic micro- and macro-fauna in what is otherwise vast and spartan sea scape. Passive continental margin cold seeps are typically attributed to the migration of hydrocarbons generated from deeply buried source rocks. Many of these seeps occur over salt tectonic provinces, where the movement of salt generates complex fault systems that can enable fluid migration or create seals and traps associated with reservoir formation. The elevated advective heat transport of the salt also produces a chimney effect directly over these structures. Here, we provide geophysical and geochemical evidence that the salt chimney effect in conjunction with diapiric faulting drives a subsurface groundwater circulation system that brings dissolved inorganic carbon, nutrient-rich deep basinal fluids, and potentially overlying seawater onto the crests of deeply buried salt diapirs. The mobilized fluids fuel methanogenic archaea locally enhancing the deep biosphere. The resulting elevated biogenic methane production, alongside the upward heat-driven fluid transport, represents a previously unrecognized mechanism of cold seep formation and regulation.
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Affiliation(s)
- Anirban Chowdhury
- Department of Geology, Saint Mary’s University, Halifax, NSB3H 3C3, Canada
| | - Gregory T. Ventura
- Department of Geology, Saint Mary’s University, Halifax, NSB3H 3C3, Canada
| | - Yaisa Owino
- Department of Geology, Saint Mary’s University, Halifax, NSB3H 3C3, Canada
| | - Ellen J. Lalk
- Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA02139
| | - Natasha MacAdam
- Nova Scotia Department of Natural Resources and Renewables, Halifax, NSB3J 3J9, Canada
| | - John M. Dooma
- Department of Geology, Saint Mary’s University, Halifax, NSB3H 3C3, Canada
| | - Shuhei Ono
- Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA02139
| | - Martin Fowler
- Applied Petroleum Technology (Canada) Ltd., Calgary, ABT3A 2M3, Canada
| | - Adam MacDonald
- Nova Scotia Department of Natural Resources and Renewables, Halifax, NSB3J 3J9, Canada
| | - Robbie Bennett
- Natural Resources Canada, Geological Survey of Canada-Atlantic, Dartmouth, NSB2Y 4A2, Canada
| | - R. Andrew MacRae
- Department of Geology, Saint Mary’s University, Halifax, NSB3H 3C3, Canada
| | - Casey R. J. Hubert
- Geomicrobiology Group, Department of Biological Sciences, University of Calgary, Calgary, ABT2N 1N4, Canada
| | - Jeremy N. Bentley
- Department of Geology, Saint Mary’s University, Halifax, NSB3H 3C3, Canada
| | - Mitchell J. Kerr
- Department of Geology, Saint Mary’s University, Halifax, NSB3H 3C3, Canada
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Junger PC, Sarmento H, Giner CR, Mestre M, Sebastián M, Morán XAG, Arístegui J, Agustí S, Duarte CM, Acinas SG, Massana R, Gasol JM, Logares R. Global biogeography of the smallest plankton across ocean depths. SCIENCE ADVANCES 2023; 9:eadg9763. [PMID: 37939185 PMCID: PMC10631730 DOI: 10.1126/sciadv.adg9763] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Accepted: 10/05/2023] [Indexed: 11/10/2023]
Abstract
Tiny ocean plankton (picoplankton) are fundamental for the functioning of the biosphere, but the ecological mechanisms shaping their biogeography were partially understood. Comprehending whether these microorganisms are structured by niche versus neutral processes is relevant in the context of global change. We investigate the ecological processes (selection, dispersal, and drift) structuring global-ocean picoplanktonic communities inhabiting the epipelagic (0 to 200 meters), mesopelagic (200 to 1000 meters), and bathypelagic (1000 to 4000 meters) zones. We found that selection decreased, while dispersal limitation increased with depth, possibly due to differences in habitat heterogeneity and dispersal barriers such as water masses and bottom topography. Picoplankton β-diversity positively correlated with environmental heterogeneity and water mass variability, but this relationship tended to be weaker for eukaryotes than for prokaryotes. Community patterns were more pronounced in the Mediterranean Sea, probably because of its cross-basin environmental heterogeneity and deep-water isolation. We conclude that different combinations of ecological mechanisms shape the biogeography of the ocean microbiome across depths.
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Affiliation(s)
- Pedro C. Junger
- Department of Hydrobiology, Universidade Federal de São Carlos (UFSCar), São Carlos, SP 13565-905, Brazil
- Programa de Pós-Graduação em Ecologia e Recursos Naturais, Centro de Ciências Biológicas e da Saúde, Universidade Federal de São Carlos (UFSCar), São Carlos, SP 13565-905, Brazil
| | - Hugo Sarmento
- Department of Hydrobiology, Universidade Federal de São Carlos (UFSCar), São Carlos, SP 13565-905, Brazil
| | - Caterina R. Giner
- Institut de Ciències del Mar (ICM), CSIC, Barcelona, Catalunya 08003, Spain
| | - Mireia Mestre
- Centro COPAS-COASTAL, Departamento de Oceanografía, Universidad de Concepción, Concepción, Chile
- Centro FONDAP de Investigación en Dinámica de Ecosistemas Marinos de Altas Latitudes (IDEAL), Valdivia, Chile
| | - Marta Sebastián
- Institut de Ciències del Mar (ICM), CSIC, Barcelona, Catalunya 08003, Spain
| | - Xosé Anxelu G. Morán
- Centro Oceanográfico de Gijón/Xixón (IEO, CSIC), Gijón/Xixón, Asturias 33212, Spain
| | - Javier Arístegui
- Instituto de Oceanografía y Cambio Global (IOCAG), Universidad de Las Palmas de Gran Canaria (ULPGC), Las Palmas de Gran Canaria 35214, Spain
| | - Susana Agustí
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center (RSRC), Thuwal 23955-6900, Saudi Arabia
| | - Carlos M. Duarte
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center (RSRC), Thuwal 23955-6900, Saudi Arabia
| | - Silvia G. Acinas
- Institut de Ciències del Mar (ICM), CSIC, Barcelona, Catalunya 08003, Spain
| | - Ramon Massana
- Institut de Ciències del Mar (ICM), CSIC, Barcelona, Catalunya 08003, Spain
| | - Josep M. Gasol
- Institut de Ciències del Mar (ICM), CSIC, Barcelona, Catalunya 08003, Spain
| | - Ramiro Logares
- Institut de Ciències del Mar (ICM), CSIC, Barcelona, Catalunya 08003, Spain
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Pavlova ON, Tupikin AE, Chernitsyna SM, Bukin YS, Lomakina AV, Pogodaeva TV, Nikonova AA, Bukin SV, Zemskaya TI, Kabilov MR. Description and Genomic Analysis of the First Facultatively Lithoautotrophic, Thermophilic Bacteria of the Genus Thermaerobacter Isolated from Low-temperature Sediments of Lake Baikal. MICROBIAL ECOLOGY 2023; 86:1604-1619. [PMID: 36717392 DOI: 10.1007/s00248-023-02182-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2022] [Accepted: 01/19/2023] [Indexed: 06/18/2023]
Abstract
Members of the genus Thermaerobacter belong to the phylum Firmicutes and all isolates characterised to date are strictly aerobic and thermophilic. They were isolated from a mud sample of the Challenger Deep in the Mariana Trench, hydrothermal vents, and silt compost. A novel thermophilic, facultatively lithoautotrophic bacteria of the genus Thermaerobacter, strain PB12/4term (=VKM B-3151T), with a metabolism that is uncharacteristic of the type species, was isolated from low-temperature surface sediments near the Posolsk Bank methane seep, Lake Baikal, Russia. The new strain grows with molecular hydrogen as electron donor, elemental sulfur, and thiosulfate as electron acceptors, and CO2/[Formula: see text] as carbon source. The genome of strain PB12/4term consists of one chromosome with a total length of 2.820.915 bp and the G+C content of the genomic DNA was 72.2%. The phylogenomic reconstruction based on 120 conserved bacterial single-copy proteins revealed that strain PB12/4term belongs to the genus Thermaerobacter within in the class Thermaerobacteria, phylum Firmicutes_E. The strain PB12/4term is closely related to Thermaerobacter subterraneus DSM 13965 (ANI=95.08%, AF=0.91) and Thermaerobacter marianensis DSM 12885 (ANI=84.98%, AF=0.77). Genomic and experimental data confirm the ability of the Thermaerobacter PB12/4term pure culture to facultatively lithotrophic growth, which is provided by the presence of [NiFe]hydrogenase enzymes that are absent in T. marianensis DSM 12885 and T. subterraneus DSM 13965. The data obtained on the physiological and biochemical differences of strain PB12/4term provide a deeper insight into the species diversity and functional activity of the genus Thermaerobacter.
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Affiliation(s)
- O N Pavlova
- Laboratory of Hydrocarbon Microbiology, Limnological Institute, Siberian Branch, Russian Academy of Sciences, Irkutsk, Russia.
| | - A E Tupikin
- SB RAS Genomics Core Facility, Institute of Chemical Biology and Fundamental Medicine, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia
| | - S M Chernitsyna
- Laboratory of Hydrocarbon Microbiology, Limnological Institute, Siberian Branch, Russian Academy of Sciences, Irkutsk, Russia
| | - Y S Bukin
- Laboratory of Genosystematics, Limnological Institute, Siberian Branch, Russian Academy of Sciences, Irkutsk, Russia
| | - A V Lomakina
- Laboratory of Hydrocarbon Microbiology, Limnological Institute, Siberian Branch, Russian Academy of Sciences, Irkutsk, Russia
| | - T V Pogodaeva
- Laboratory of Hydrochemistry and Atmosphere Chemistry, Limnological Institute, Siberian Branch, Russian Academy of Sciences, Irkutsk, Russia
| | - A A Nikonova
- Laboratory of Chromatography, Limnological Institute, Siberian Branch, Russian Academy of Sciences, Irkutsk, Russia
| | - S V Bukin
- Laboratory of Hydrocarbon Microbiology, Limnological Institute, Siberian Branch, Russian Academy of Sciences, Irkutsk, Russia
| | - T I Zemskaya
- Laboratory of Hydrocarbon Microbiology, Limnological Institute, Siberian Branch, Russian Academy of Sciences, Irkutsk, Russia
| | - M R Kabilov
- SB RAS Genomics Core Facility, Institute of Chemical Biology and Fundamental Medicine, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia
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Ferguson DK, Li C, Chakraborty A, Gittins DA, Fowler M, Webb J, Campbell C, Morrison N, MacDonald A, Hubert CRJ. Multi-year seabed environmental baseline in deep-sea offshore oil prospective areas established using microbial biodiversity. MARINE POLLUTION BULLETIN 2023; 194:115308. [PMID: 37517246 DOI: 10.1016/j.marpolbul.2023.115308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 07/14/2023] [Accepted: 07/16/2023] [Indexed: 08/01/2023]
Abstract
Microorganisms are the ocean's first responders to marine pollution events, yet baseline studies rarely focus on microbial communities. Temporal and spatial microbial biodiversity baselines were established using bacterial 16S rRNA gene amplicon sequencing of seafloor sediments in a deep-water oil prospective area along the Scotian Slope off Canada's east coast sampled during 2015-2018. Bacterial diversity was generally similar in space and time, with members of the family Woeseiaceae detected consistently in >1 % relative abundance, similar to seabed sediments in other parts of the world. Anomalous biodiversity results at one site featured lower Woeseiaceae as well as higher levels of bacterial groups specifically associated with cold seeps such as Aminicenantes. This was unexpected given that site selection was based on sediment geochemistry not revealing any petroleum hydrocarbons in these locations. This finding highlights the sensitivity and specificity of microbial DNA sequencing in environmental monitoring. Microbiome assessments like this one represent an important strategy for incorporating microbial biodiversity as a new and useful metric for establishing robust environmental baselines that are necessary for understanding ecosystem responses to marine pollution.
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Affiliation(s)
- Deidra K Ferguson
- Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada.
| | - Carmen Li
- Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada
| | - Anirban Chakraborty
- Department of Biological Sciences, Idaho State University, Pocatello, ID, USA
| | - Daniel A Gittins
- Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada
| | - Martin Fowler
- Applied Petroleum Technology Canada, Calgary, Alberta, Canada
| | - Jamie Webb
- Applied Petroleum Technology Canada, Calgary, Alberta, Canada
| | - Calvin Campbell
- Natural Resources Canada, Geological Survey of Canada-Atlantic, Dartmouth, Nova Scotia, Canada
| | - Natasha Morrison
- Nova Scotia Department of Natural Resources and Renewables, Government of Nova Scotia, Halifax, Nova Scotia, Canada
| | - Adam MacDonald
- Nova Scotia Department of Natural Resources and Renewables, Government of Nova Scotia, Halifax, Nova Scotia, Canada
| | - Casey R J Hubert
- Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada.
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Hallsworth JE, Udaondo Z, Pedrós‐Alió C, Höfer J, Benison KC, Lloyd KG, Cordero RJB, de Campos CBL, Yakimov MM, Amils R. Scientific novelty beyond the experiment. Microb Biotechnol 2023; 16:1131-1173. [PMID: 36786388 PMCID: PMC10221578 DOI: 10.1111/1751-7915.14222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 01/09/2023] [Accepted: 01/11/2023] [Indexed: 02/15/2023] Open
Abstract
Practical experiments drive important scientific discoveries in biology, but theory-based research studies also contribute novel-sometimes paradigm-changing-findings. Here, we appraise the roles of theory-based approaches focusing on the experiment-dominated wet-biology research areas of microbial growth and survival, cell physiology, host-pathogen interactions, and competitive or symbiotic interactions. Additional examples relate to analyses of genome-sequence data, climate change and planetary health, habitability, and astrobiology. We assess the importance of thought at each step of the research process; the roles of natural philosophy, and inconsistencies in logic and language, as drivers of scientific progress; the value of thought experiments; the use and limitations of artificial intelligence technologies, including their potential for interdisciplinary and transdisciplinary research; and other instances when theory is the most-direct and most-scientifically robust route to scientific novelty including the development of techniques for practical experimentation or fieldwork. We highlight the intrinsic need for human engagement in scientific innovation, an issue pertinent to the ongoing controversy over papers authored using/authored by artificial intelligence (such as the large language model/chatbot ChatGPT). Other issues discussed are the way in which aspects of language can bias thinking towards the spatial rather than the temporal (and how this biased thinking can lead to skewed scientific terminology); receptivity to research that is non-mainstream; and the importance of theory-based science in education and epistemology. Whereas we briefly highlight classic works (those by Oakes Ames, Francis H.C. Crick and James D. Watson, Charles R. Darwin, Albert Einstein, James E. Lovelock, Lynn Margulis, Gilbert Ryle, Erwin R.J.A. Schrödinger, Alan M. Turing, and others), the focus is on microbiology studies that are more-recent, discussing these in the context of the scientific process and the types of scientific novelty that they represent. These include several studies carried out during the 2020 to 2022 lockdowns of the COVID-19 pandemic when access to research laboratories was disallowed (or limited). We interviewed the authors of some of the featured microbiology-related papers and-although we ourselves are involved in laboratory experiments and practical fieldwork-also drew from our own research experiences showing that such studies can not only produce new scientific findings but can also transcend barriers between disciplines, act counter to scientific reductionism, integrate biological data across different timescales and levels of complexity, and circumvent constraints imposed by practical techniques. In relation to urgent research needs, we believe that climate change and other global challenges may require approaches beyond the experiment.
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Affiliation(s)
- John E. Hallsworth
- Institute for Global Food Security, School of Biological SciencesQueen's University BelfastBelfastUK
| | - Zulema Udaondo
- Department of Biomedical InformaticsUniversity of Arkansas for Medical SciencesLittle RockArkansasUSA
| | - Carlos Pedrós‐Alió
- Department of Systems BiologyCentro Nacional de Biotecnología (CSIC)MadridSpain
| | - Juan Höfer
- Escuela de Ciencias del MarPontificia Universidad Católica de ValparaísoValparaísoChile
| | - Kathleen C. Benison
- Department of Geology and GeographyWest Virginia UniversityMorgantownWest VirginiaUSA
| | - Karen G. Lloyd
- Microbiology DepartmentUniversity of TennesseeKnoxvilleTennesseeUSA
| | - Radamés J. B. Cordero
- Department of Molecular Microbiology and ImmunologyJohns Hopkins Bloomberg School of Public HealthBaltimoreMarylandUSA
| | - Claudia B. L. de Campos
- Institute of Science and TechnologyUniversidade Federal de Sao Paulo (UNIFESP)São José dos CamposSPBrazil
| | | | - Ricardo Amils
- Department of Molecular Biology, Centro de Biología Molecular Severo Ochoa (CSIC‐UAM)Nicolás Cabrera n° 1, Universidad Autónoma de MadridMadridSpain
- Department of Planetology and HabitabilityCentro de Astrobiología (INTA‐CSIC)Torrejón de ArdozSpain
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Environmental Selection and Biogeography Shape the Microbiome of Subsurface Petroleum Reservoirs. mSystems 2023; 8:e0088422. [PMID: 36786580 PMCID: PMC10134868 DOI: 10.1128/msystems.00884-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
Abstract
Petroleum reservoirs within the deep biosphere are extreme environments inhabited by diverse microbial communities and represent biogeochemical hot spots in the subsurface. Despite the ecological and industrial importance of oil reservoir microbiomes, systematic study of core microbial taxa and their associated genomic attributes spanning different environmental conditions is limited. Here, we compile and compare 343 16S rRNA gene amplicon libraries and 25 shotgun metagenomic libraries from oil reservoirs in different parts of the world to test for the presence of core taxa and functions. These oil reservoir libraries do not share any core taxa at the species, genus, family, or order levels, and Gammaproteobacteria was the only taxonomic class detected in all samples. Instead, taxonomic composition varies among reservoirs with different physicochemical characteristics and with geographic distance highlighting environmental selection and biogeography in these deep biosphere habitats. Gene-centric metagenomic analysis reveals a functional core of metabolic pathways including carbon acquisition and energy-yielding strategies consistent with biogeochemical cycling in other subsurface environments. Genes for anaerobic hydrocarbon degradation are observed in a subset of the samples and are therefore not considered to represent core functions in oil reservoirs despite hydrocarbons representing an abundant source of carbon in these deep biosphere settings. Overall, this work reveals common and divergent features of oil reservoir microbiomes that are shaped by and responsive to environmental factors, highlighting controls on subsurface microbial community assembly. IMPORTANCE This comprehensive analysis showcases how environmental selection and geographic distance influence the microbiome of subsurface petroleum reservoirs. We reveal substantial differences in the taxonomy of the inhabiting microbes but shared metabolic function between reservoirs with different in situ temperatures and between reservoirs separated by large distances. The study helps understand and advance the field of deep biosphere science by providing an ecological framework and footing for geologists, chemists, and microbiologists studying these habitats to elucidate major controls on deep biosphere microbial ecology.
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Lazar CS, Schmidt F, Elvert M, Heuer VB, Hinrichs KU, Teske AP. Microbial diversity gradients in the geothermal mud volcano underlying the hypersaline Urania Basin. Front Microbiol 2022; 13:1043414. [PMID: 36620052 PMCID: PMC9812581 DOI: 10.3389/fmicb.2022.1043414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 12/01/2022] [Indexed: 12/24/2022] Open
Abstract
Mud volcanoes transport deep fluidized sediment and their microbial communities and thus provide a window into the deep biosphere. However, mud volcanoes are commonly sampled at the surface and not probed at greater depths, with the consequence that their internal geochemistry and microbiology remain hidden from view. Urania Basin, a hypersaline seafloor basin in the Mediterranean, harbors a mud volcano that erupts fluidized mud into the brine. The vertical mud pipe was amenable to shipboard Niskin bottle and multicorer sampling and provided an opportunity to investigate the downward sequence of bacterial and archaeal communities of the Urania Basin brine, fluid mud layers and consolidated subsurface sediments using 16S rRNA gene sequencing. These microbial communities show characteristic, habitat-related trends as they change throughout the sample series, from extremely halophilic bacteria (KB1) and archaea (Halodesulfoarchaeum spp.) in the brine, toward moderately halophilic and thermophilic endospore-forming bacteria and uncultured archaeal lineages in the mud fluid, and finally ending in aromatics-oxidizing bacteria, uncultured spore formers, and heterotrophic subsurface archaea (Thermoplasmatales, Bathyarchaeota, and Lokiarcheota) in the deep subsurface sediment at the bottom of the mud volcano. Since these bacterial and archaeal lineages are mostly anaerobic heterotrophic fermenters, the microbial ecosystem in the brine and fluidized mud functions as a layered fermenter for the degradation of sedimentary biomass and hydrocarbons. By spreading spore-forming, thermophilic Firmicutes during eruptions, the Urania Basin mud volcano likely functions as a source of endospores that occur widely in cold seafloor sediments.
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Affiliation(s)
- Cassandre Sara Lazar
- Department of Biological Sciences, Université du Québec à Montréal, Montréal, QC, Canada
| | - Frauke Schmidt
- Organic Geochemistry Group, Department of Geosciences, MARUM Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | - Marcus Elvert
- Organic Geochemistry Group, Department of Geosciences, MARUM Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | - Verena B. Heuer
- Organic Geochemistry Group, Department of Geosciences, MARUM Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | - Kai-Uwe Hinrichs
- Organic Geochemistry Group, Department of Geosciences, MARUM Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | - Andreas P. Teske
- Department of Earth, Marine and Environmental Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
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9
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Milojevic T, Cramm MA, Hubert CRJ, Westall F. "Freezing" Thermophiles: From One Temperature Extreme to Another. Microorganisms 2022; 10:microorganisms10122417. [PMID: 36557670 PMCID: PMC9782878 DOI: 10.3390/microorganisms10122417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 11/23/2022] [Accepted: 11/30/2022] [Indexed: 12/12/2022] Open
Abstract
New detections of thermophiles in psychrobiotic (i.e., bearing cold-tolerant life forms) marine and terrestrial habitats including Arctic marine sediments, Antarctic accretion ice, permafrost, and elsewhere are continually being reported. These microorganisms present great opportunities for microbial ecologists to examine biogeographical processes for spore-formers and non-spore-formers alike, including dispersal histories connecting warm and cold biospheres. In this review, we examine different examples of thermophiles in cryobiotic locations, and highlight exploration of thermophiles at cold temperatures under laboratory conditions. The survival of thermophiles in psychrobiotic environments provokes novel considerations of physiological and molecular mechanisms underlying natural cryopreservation of microorganisms. Cultures of thermophiles maintained at low temperature may serve as a non-sporulating laboratory model for further exploration of metabolic potential of thermophiles at psychrobiotic temperatures, as well as for elucidating molecular mechanisms behind natural preservation and adaptation to psychrobiotic environments. These investigations are highly relevant for the search for life on other cold and icy planets in the Solar System, such as Mars, Europa and Enceladus.
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Affiliation(s)
- Tetyana Milojevic
- Exobiology Group, CNRS-Centre de Biophysique Moléculaire, University of Orléans, Rue Charles Sadron, CEDEX 2, 45071 Orléans, France
- Correspondence: ; Tel.: +33-2-3825-5548
| | - Margaret Anne Cramm
- Geomicrobiology Group, Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, AB T2N 1N4, Canada
| | - Casey R. J. Hubert
- Geomicrobiology Group, Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, AB T2N 1N4, Canada
| | - Frances Westall
- Exobiology Group, CNRS-Centre de Biophysique Moléculaire, Rue Charles Sadron, CEDEX 2, 45071 Orléans, France
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