1
|
Suzuki S, Ishii S, Chadwick GL, Tanaka Y, Kouzuma A, Watanabe K, Inagaki F, Albertsen M, Nielsen PH, Nealson KH. A non-methanogenic archaeon within the order Methanocellales. Nat Commun 2024; 15:4858. [PMID: 38871712 DOI: 10.1038/s41467-024-48185-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Accepted: 04/22/2024] [Indexed: 06/15/2024] Open
Abstract
Serpentinization, a geochemical process found on modern and ancient Earth, provides an ultra-reducing environment that can support microbial methanogenesis and acetogenesis. Several groups of archaea, such as the order Methanocellales, are characterized by their ability to produce methane. Here, we generate metagenomic sequences from serpentinized springs in The Cedars, California, and construct a circularized metagenome-assembled genome of a Methanocellales archaeon, termed Met12, that lacks essential methanogenesis genes. The genome includes genes for an acetyl-CoA pathway, but lacks genes encoding methanogenesis enzymes such as methyl-coenzyme M reductase, heterodisulfide reductases and hydrogenases. In situ transcriptomic analyses reveal high expression of a multi-heme c-type cytochrome, and heterologous expression of this protein in a model bacterium demonstrates that it is capable of accepting electrons. Our results suggest that Met12, within the order Methanocellales, is not a methanogen but a CO2-reducing, electron-fueled acetogen without electron bifurcation.
Collapse
Affiliation(s)
- Shino Suzuki
- Geobiology and Astrobiology Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama, Japan.
- Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency (JAXA), Sagamihara, Kanagawa, Japan.
- School of Physical Sciences, SOKENDAI (Graduate University for Advanced Studies), Sagamihara, Kanagawa, Japan.
- Institute for Extra-cutting-edge Science and Technology Avant-garde Research (X-star), Japan Agency for Marine and Earth Science and Technology (JAMSTEC), Yokosuka, Kanagawa, Japan.
| | - Shun'ichi Ishii
- Institute for Extra-cutting-edge Science and Technology Avant-garde Research (X-star), Japan Agency for Marine and Earth Science and Technology (JAMSTEC), Yokosuka, Kanagawa, Japan.
| | - Grayson L Chadwick
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA, USA
| | - Yugo Tanaka
- School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, Japan
| | - Atsushi Kouzuma
- School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, Japan
| | - Kazuya Watanabe
- School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, Japan
| | - Fumio Inagaki
- Advanced Institute for Marine Ecosystem Change (WPI-AIMEC), JAMSTEC, Yokohama, Kanagawa, Japan
- Department of Earth Science, Graduate School of Science, Tohoku University, Sendai, Miyagi, Japan
| | - Mads Albertsen
- Center for Microbial Communities, Aalborg University, Aalborg, Denmark
| | - Per H Nielsen
- Center for Microbial Communities, Aalborg University, Aalborg, Denmark
| | - Kenneth H Nealson
- Department of Earth Sciences, University of Southern California, Los Angeles, CA, USA
| |
Collapse
|
2
|
Utzman PH, Mays VP, Miller BC, Fairbanks MC, Brazelton WJ, Horvath MP. Metagenome mining and functional analysis reveal oxidized guanine DNA repair at the Lost City Hydrothermal Field. PLoS One 2024; 19:e0284642. [PMID: 38718041 PMCID: PMC11078426 DOI: 10.1371/journal.pone.0284642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Accepted: 04/16/2024] [Indexed: 05/12/2024] Open
Abstract
The GO DNA repair system protects against GC → TA mutations by finding and removing oxidized guanine. The system is mechanistically well understood but its origins are unknown. We searched metagenomes and abundantly found the genes encoding GO DNA repair at the Lost City Hydrothermal Field (LCHF). We recombinantly expressed the final enzyme in the system to show MutY homologs function to suppress mutations. Microbes at the LCHF thrive without sunlight, fueled by the products of geochemical transformations of seafloor rocks, under conditions believed to resemble a young Earth. High levels of the reductant H2 and low levels of O2 in this environment raise the question, why are resident microbes equipped to repair damage caused by oxidative stress? MutY genes could be assigned to metagenome-assembled genomes (MAGs), and thereby associate GO DNA repair with metabolic pathways that generate reactive oxygen, nitrogen and sulfur species. Our results indicate that cell-based life was under evolutionary pressure to cope with oxidized guanine well before O2 levels rose following the great oxidation event.
Collapse
Affiliation(s)
- Payton H. Utzman
- School of Biological Sciences, University of Utah, Salt Lake City, Utah, United States of America
| | - Vincent P. Mays
- School of Biological Sciences, University of Utah, Salt Lake City, Utah, United States of America
| | - Briggs C. Miller
- School of Biological Sciences, University of Utah, Salt Lake City, Utah, United States of America
| | - Mary C. Fairbanks
- School of Biological Sciences, University of Utah, Salt Lake City, Utah, United States of America
| | - William J. Brazelton
- School of Biological Sciences, University of Utah, Salt Lake City, Utah, United States of America
| | - Martin P. Horvath
- School of Biological Sciences, University of Utah, Salt Lake City, Utah, United States of America
| |
Collapse
|
3
|
Xu J, Zhao R, Liu A, Li L, Li S, Li Y, Qu M, Di Y. To live or die: "Fine-tuning" adaptation revealed by systemic analyses in symbiotic bathymodiolin mussels from diverse deep-sea extreme ecosystems. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 917:170434. [PMID: 38278266 DOI: 10.1016/j.scitotenv.2024.170434] [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: 10/16/2023] [Revised: 01/21/2024] [Accepted: 01/23/2024] [Indexed: 01/28/2024]
Abstract
Hydrothermal vents (HVs) and cold seeps (CSs) are typical deep-sea extreme ecosystems with their own geochemical characteristics to supply the unique living conditions for local communities. Once HVs or CSs stop emission, the dramatic environmental change would pose survival risks to deep-sea organisms. Up to now, limited knowledge has been available to understand the biological responses and adaptive strategy to the extreme environments and their transition from active to extinct stage, mainly due to the technical difficulties and lack of representative organisms. In this study, bathymodiolin mussels, the dominant and successful species surviving in diverse deep-sea extreme ecosystems, were collected from active and extinct HVs (Southwest Indian Ocean) or CSs (South China Sea) via two individual cruises. The transcriptomic analysis and determination of multiple biological indexes in stress defense and metabolic systems were conducted in both gills and digestive glands of mussels, together with the metagenomic analysis of symbionts in mussels. The results revealed the ecosystem- and tissue-specific transcriptional regulation in mussels, addressing the autologous adaptations in antioxidant defense, energy utilization and key compounds (i.e. sulfur) metabolism. In detail, the successful antioxidant defense contributed to conquering the oxidative stress induced during the unavoidable metabolism of xenobiotics commonly existing in the extreme ecosystems; changes in metabolic rate functioned to handle toxic matters in different surroundings; upregulated gene expression of sulfide:quinone oxidoreductase indicated an active sulfide detoxification in mussels from HVs and active stage of HVs & CSs. Coordinately, a heterologous adaptation, characterized by the functional compensation between symbionts and mussels in energy utilization, sulfur and carbon metabolism, was also evidenced by the bacterial metagenomic analysis. Taken together, a new insight was proposed that symbiotic bathymodiolin mussels would develop a "finetuning" strategy combining the autologous and heterologous regulations to fulfill the efficient and effective adaptations for successful survival.
Collapse
Affiliation(s)
- Jianzhou Xu
- Ocean College, Zhejiang University, Zhoushan 316000, China; Hainan Institute of Zhejiang University, Sanya 572024, China
| | - Ruoxuan Zhao
- Ocean College, Zhejiang University, Zhoushan 316000, China
| | - Ao Liu
- Ocean College, Zhejiang University, Zhoushan 316000, China
| | - Liya Li
- Ocean College, Zhejiang University, Zhoushan 316000, China; Hainan Institute of Zhejiang University, Sanya 572024, China
| | - Shuimei Li
- Ocean College, Zhejiang University, Zhoushan 316000, China
| | - Yichen Li
- Ocean College, Zhejiang University, Zhoushan 316000, China
| | - Mengjie Qu
- Ocean College, Zhejiang University, Zhoushan 316000, China; Hainan Institute of Zhejiang University, Sanya 572024, China
| | - Yanan Di
- Ocean College, Zhejiang University, Zhoushan 316000, China; Hainan Institute of Zhejiang University, Sanya 572024, China.
| |
Collapse
|
4
|
Mara P, Geller-McGrath D, Edgcomb V, Beaudoin D, Morono Y, Teske A. Metagenomic profiles of archaea and bacteria within thermal and geochemical gradients of the Guaymas Basin deep subsurface. Nat Commun 2023; 14:7768. [PMID: 38012208 PMCID: PMC10681998 DOI: 10.1038/s41467-023-43296-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Accepted: 11/02/2023] [Indexed: 11/29/2023] Open
Abstract
Previous studies of microbial communities in subseafloor sediments reported that microbial abundance and diversity decrease with sediment depth and age, and microbes dominating at depth tend to be a subset of the local seafloor community. However, the existence of geographically widespread, subsurface-adapted specialists is also possible. Here, we use metagenomic and metatranscriptomic analyses of the hydrothermally heated, sediment layers of Guaymas Basin (Gulf of California, Mexico) to examine the distribution and activity patterns of bacteria and archaea along thermal, geochemical and cell count gradients. We find that the composition and distribution of metagenome-assembled genomes (MAGs), dominated by numerous lineages of Chloroflexota and Thermoproteota, correlate with biogeochemical parameters as long as temperatures remain moderate, but downcore increasing temperatures beyond ca. 45 ºC override other factors. Consistently, MAG size and diversity decrease with increasing temperature, indicating a downcore winnowing of the subsurface biosphere. By contrast, specific archaeal MAGs within the Thermoproteota and Hadarchaeota increase in relative abundance and in recruitment of transcriptome reads towards deeper, hotter sediments, marking the transition towards a specialized deep, hot biosphere.
Collapse
Affiliation(s)
- Paraskevi Mara
- Geology and Geophysics Department, Woods Hole Oceanographic Institution, Woods Hole, MA, 02543, USA
| | - David Geller-McGrath
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA, 02543, USA
| | - Virginia Edgcomb
- Geology and Geophysics Department, Woods Hole Oceanographic Institution, Woods Hole, MA, 02543, USA
| | - David Beaudoin
- Geology and Geophysics Department, Woods Hole Oceanographic Institution, Woods Hole, MA, 02543, USA
| | - Yuki Morono
- Kochi Institute for Core Sample Research, Institute for Extra-cutting-edge Science and Technology Avantgarde Research (X-STAR), Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Monobe, Nankoku, Kochi, Japan
| | - Andreas Teske
- Department of Earth, Marine and Environmental Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA.
| |
Collapse
|
5
|
Mrnjavac N, Wimmer JLE, Brabender M, Schwander L, Martin WF. The Moon-Forming Impact and the Autotrophic Origin of Life. Chempluschem 2023; 88:e202300270. [PMID: 37812146 PMCID: PMC7615287 DOI: 10.1002/cplu.202300270] [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: 06/05/2023] [Revised: 09/29/2023] [Accepted: 10/03/2023] [Indexed: 10/10/2023]
Abstract
The Moon-forming impact vaporized part of Earth's mantle, and turned the rest into a magma ocean, from which carbon dioxide degassed into the atmosphere, where it stayed until water rained out to form the oceans. The rain dissolved CO2 and made it available to react with transition metal catalysts in the Earth's crust so as to ultimately generate the organic compounds that form the backbone of microbial metabolism. The Moon-forming impact was key in building a planet with the capacity to generate life in that it converted carbon on Earth into a homogeneous and accessible substrate for organic synthesis. Today all ecosystems, without exception, depend upon primary producers, organisms that fix CO2 . According to theories of autotrophic origin, it has always been that way, because autotrophic theories posit that the first forms of life generated all the molecules needed to build a cell from CO2 , forging a direct line of continuity between Earth's initial CO2 -rich atmosphere and the first microorganisms. By modern accounts these were chemolithoautotrophic archaea and bacteria that initially colonized the crust and still inhabit that environment today.
Collapse
Affiliation(s)
- Natalia Mrnjavac
- Department of Biology Institute for Molecular Evolution Heinrich Heine University Duesseldorf Universitaetsstr. 1, 40225 Düsseldorf (Germany)
| | - Jessica L. E. Wimmer
- Department of Biology Institute for Molecular Evolution Heinrich Heine University Duesseldorf Universitaetsstr. 1, 40225 Düsseldorf (Germany)
| | - Max Brabender
- Department of Biology Institute for Molecular Evolution Heinrich Heine University Duesseldorf Universitaetsstr. 1, 40225 Düsseldorf (Germany)
| | - Loraine Schwander
- Department of Biology Institute for Molecular Evolution Heinrich Heine University Duesseldorf Universitaetsstr. 1, 40225 Düsseldorf (Germany)
| | - William F. Martin
- Department of Biology Institute for Molecular Evolution Heinrich Heine University Duesseldorf Universitaetsstr. 1, 40225 Düsseldorf (Germany)
| |
Collapse
|
6
|
Schwander L, Brabender M, Mrnjavac N, Wimmer JLE, Preiner M, Martin WF. Serpentinization as the source of energy, electrons, organics, catalysts, nutrients and pH gradients for the origin of LUCA and life. Front Microbiol 2023; 14:1257597. [PMID: 37854333 PMCID: PMC10581274 DOI: 10.3389/fmicb.2023.1257597] [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: 07/12/2023] [Accepted: 09/04/2023] [Indexed: 10/20/2023] Open
Abstract
Serpentinization in hydrothermal vents is central to some autotrophic theories for the origin of life because it generates compartments, reductants, catalysts and gradients. During the process of serpentinization, water circulates through hydrothermal systems in the crust where it oxidizes Fe (II) in ultramafic minerals to generate Fe (III) minerals and H2. Molecular hydrogen can, in turn, serve as a freely diffusible source of electrons for the reduction of CO2 to organic compounds, provided that suitable catalysts are present. Using catalysts that are naturally synthesized in hydrothermal vents during serpentinization H2 reduces CO2 to formate, acetate, pyruvate, and methane. These compounds represent the backbone of microbial carbon and energy metabolism in acetogens and methanogens, strictly anaerobic chemolithoautotrophs that use the acetyl-CoA pathway of CO2 fixation and that inhabit serpentinizing environments today. Serpentinization generates reduced carbon, nitrogen and - as newer findings suggest - reduced phosphorous compounds that were likely conducive to the origins process. In addition, it gives rise to inorganic microcompartments and proton gradients of the right polarity and of sufficient magnitude to support chemiosmotic ATP synthesis by the rotor-stator ATP synthase. This would help to explain why the principle of chemiosmotic energy harnessing is more conserved (older) than the machinery to generate ion gradients via pumping coupled to exergonic chemical reactions, which in the case of acetogens and methanogens involve H2-dependent CO2 reduction. Serpentinizing systems exist in terrestrial and deep ocean environments. On the early Earth they were probably more abundant than today. There is evidence that serpentinization once occurred on Mars and is likely still occurring on Saturn's icy moon Enceladus, providing a perspective on serpentinization as a source of reductants, catalysts and chemical disequilibrium for life on other worlds.
Collapse
Affiliation(s)
- Loraine Schwander
- Institute of Molecular Evolution, Biology Department, Math. -Nat. Faculty, Heinrich-Heine-Universität, Düsseldorf, Germany
| | - Max Brabender
- Institute of Molecular Evolution, Biology Department, Math. -Nat. Faculty, Heinrich-Heine-Universität, Düsseldorf, Germany
| | - Natalia Mrnjavac
- Institute of Molecular Evolution, Biology Department, Math. -Nat. Faculty, Heinrich-Heine-Universität, Düsseldorf, Germany
| | - Jessica L. E. Wimmer
- Institute of Molecular Evolution, Biology Department, Math. -Nat. Faculty, Heinrich-Heine-Universität, Düsseldorf, Germany
| | - Martina Preiner
- Microcosm Earth Center, Max Planck Institute for Terrestrial Microbiology and Philipps-Universität, Marburg, Germany
| | - William F. Martin
- Institute of Molecular Evolution, Biology Department, Math. -Nat. Faculty, Heinrich-Heine-Universität, Düsseldorf, Germany
| |
Collapse
|
7
|
Weber JM, Marlin TC, Prakash M, Teece BL, Dzurilla K, Barge LM. A Review on Hypothesized Metabolic Pathways on Europa and Enceladus: Space-Flight Detection Considerations. Life (Basel) 2023; 13:1726. [PMID: 37629583 PMCID: PMC10456045 DOI: 10.3390/life13081726] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 08/01/2023] [Accepted: 08/07/2023] [Indexed: 08/27/2023] Open
Abstract
Enceladus and Europa, icy moons of Saturn and Jupiter, respectively, are believed to be habitable with liquid water oceans and therefore are of interest for future life detection missions and mission concepts. With the limited data from missions to these moons, many studies have sought to better constrain these conditions. With these constraints, researchers have, based on modeling and experimental studies, hypothesized a number of possible metabolisms that could exist on Europa and Enceladus if these worlds host life. The most often hypothesized metabolisms are methanogenesis for Enceladus and methane oxidation/sulfate reduction on Europa. Here, we outline, review, and compare the best estimated conditions of each moon's ocean. We then discuss the hypothetical metabolisms that have been suggested to be present on these moons, based on laboratory studies and Earth analogs. We also detail different detection methods that could be used to detect these hypothetical metabolic reactions and make recommendations for future research and considerations for future missions.
Collapse
Affiliation(s)
- Jessica M. Weber
- NASA Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA (B.L.T.); (K.D.); (L.M.B.)
| | | | | | | | | | | |
Collapse
|
8
|
Popall RM, Postec A, Lecoeuvre A, Quéméneur M, Erauso G. Metabolic challenges and key players in serpentinite-hosted microbial ecosystems. Front Microbiol 2023; 14:1197823. [PMID: 37555067 PMCID: PMC10404738 DOI: 10.3389/fmicb.2023.1197823] [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: 03/31/2023] [Accepted: 06/29/2023] [Indexed: 08/10/2023] Open
Abstract
Serpentinite-hosted systems are amongst the most challenging environments for life on Earth. Serpentinization, a geochemical alteration of exposed ultramafic rock, produces hydrothermal fluids enriched in abiotically derived hydrogen (H2), methane (CH4), and small organic molecules. The hyperalkaline pH of these fluids poses a great challenge for metabolic energy and nutrient acquisition, curbing the cellular membrane potential and limiting electron acceptor, carbon, and phosphorous availability. Nevertheless, serpentinization supports the growth of diverse microbial communities whose metabolic make-up might shed light on the beginning of life on Earth and potentially elsewhere. Here, we outline current hypotheses on metabolic energy production, carbon fixation, and nutrient acquisition in serpentinizing environments. A taxonomic survey is performed for each important metabolic function, highlighting potential key players such as H2 and CH4 cycling Serpentinimonas, Hydrogenophaga, Methanobacteriales, Methanosarcinales, and novel candidate phyla. Methodological biases of the available data and future approaches are discussed.
Collapse
Affiliation(s)
| | | | | | | | - Gaël Erauso
- Aix-Marseille Univ, Univ Toulon, CNRS, IRD, MIO, Marseille, France
| |
Collapse
|
9
|
Coskun ÖK, Gomez-Saez GV, Beren M, Ozcan D, Hosgormez H, Einsiedl F, Orsi WD. Carbon metabolism and biogeography of candidate phylum " Candidatus Bipolaricaulota" in geothermal environments of Biga Peninsula, Turkey. Front Microbiol 2023; 14:1063139. [PMID: 36910224 PMCID: PMC9992828 DOI: 10.3389/fmicb.2023.1063139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Accepted: 01/17/2023] [Indexed: 02/25/2023] Open
Abstract
Terrestrial hydrothermal springs and aquifers are excellent sites to study microbial biogeography because of their high physicochemical heterogeneity across relatively limited geographic regions. In this study, we performed 16S rRNA gene sequencing and metagenomic analyses of the microbial diversity of 11 different geothermal aquifers and springs across the tectonically active Biga Peninsula (Turkey). Across geothermal settings ranging in temperature from 43 to 79°C, one of the most highly represented groups in both 16S rRNA gene and metagenomic datasets was affiliated with the uncultivated phylum "Candidatus Bipolaricaulota" (former "Ca. Acetothermia" and OP1 division). The highest relative abundance of "Ca. Bipolaricaulota" was observed in a 68°C geothermal brine sediment, where it dominated the microbial community, representing 91% of all detectable 16S rRNA genes. Correlation analysis of "Ca. Bipolaricaulota" operational taxonomic units (OTUs) with physicochemical parameters indicated that salinity was the strongest environmental factor measured associated with the distribution of this novel group in geothermal fluids. Correspondingly, analysis of 23 metagenome-assembled genomes (MAGs) revealed two distinct groups of "Ca. Bipolaricaulota" MAGs based on the differences in carbon metabolism: one group encoding the bacterial Wood-Ljungdahl pathway (WLP) for H2 dependent CO2 fixation is selected for at lower salinities, and a second heterotrophic clade that lacks the WLP that was selected for under hypersaline conditions in the geothermal brine sediment. In conclusion, our results highlight that the biogeography of "Ca. Bipolaricaulota" taxa is strongly correlated with salinity in hydrothermal ecosystems, which coincides with key differences in carbon acquisition strategies. The exceptionally high relative abundance of apparently heterotrophic representatives of this novel candidate Phylum in geothermal brine sediment observed here may help to guide future enrichment experiments to obtain representatives in pure culture.
Collapse
Affiliation(s)
- Ömer K Coskun
- Department of Earth and Environmental Sciences, Paleontology and Geobiology, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Gonzalo V Gomez-Saez
- Department of Earth and Environmental Sciences, Paleontology and Geobiology, Ludwig-Maximilians-Universität München, Munich, Germany.,GeoBio-CenterLMU, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Murat Beren
- Department of Geological Engineering, Istanbul University-Cerrahpasa, Istanbul, Türkiye
| | - Dogacan Ozcan
- Department of Geological Engineering, Istanbul University-Cerrahpasa, Istanbul, Türkiye
| | - Hakan Hosgormez
- Department of Geological Engineering, Istanbul University-Cerrahpasa, Istanbul, Türkiye
| | - Florian Einsiedl
- Chair of Hydrogeology, TUM School of Engineering and Design, Technical University of Munich, Munich, Germany
| | - William D Orsi
- Department of Earth and Environmental Sciences, Paleontology and Geobiology, Ludwig-Maximilians-Universität München, Munich, Germany.,GeoBio-CenterLMU, Ludwig-Maximilians-Universität München, Munich, Germany
| |
Collapse
|
10
|
Holden JF, Sistu H. Formate and hydrogen in hydrothermal vents and their use by extremely thermophilic methanogens and heterotrophs. Front Microbiol 2023; 14:1093018. [PMID: 36950162 PMCID: PMC10025317 DOI: 10.3389/fmicb.2023.1093018] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 02/20/2023] [Indexed: 03/08/2023] Open
Abstract
Extremely thermophilic methanogens in the Methanococci and heterotrophs in the Thermococci are common in deep-sea hydrothermal vents. All Methanococci use H2 as an electron donor, and a few species can also use formate. Most Methanococci have a coenzyme F420-reducing formate dehydrogenase. All Thermococci reduce S0 but have hydrogenases and produce H2 in the absence of S0. Some Thermococci have formate hydrogenlyase (Fhl) that reversibly converts H2 and CO2 to formate or an NAD(P)+-reducing formate dehydrogenase (Nfd). Questions remain if Methanococci or Thermococci use or produce formate in nature, why only certain species can grow on or produce formate, and what the physiological role of formate is? Formate forms abiotically in hydrothermal fluids through chemical equilibrium with primarily H2, CO2, and CO and is strongly dependent upon H2 concentration, pH, and temperature. Formate concentrations are highest in hydrothermal fluids where H2 concentrations are also high, such as in ultramafic systems where serpentinization reactions occur. In nature, Methanococci are likely to use formate as an electron donor when H2 is limiting. Thermococci with Fhl likely convert H2 and CO2 to formate when H2 concentrations become inhibitory for growth. They are unlikely to grow on formate in nature unless formate is more abundant than H2 in the environment. Nearly all Methanococci and Thermococci have a gene for at least one formate dehydrogenase catalytic subunit, which may be used to provide free formate for de novo purine biosynthesis. However, only species with a membrane-bound formate transporter can grow on or secrete formate. Interspecies H2 transfer occurs between Thermococci and Methanococci. This and putative interspecies formate transfer may support Methanococci in low H2 environments, which in turn may prevent growth inhibition of Thermococci by its own H2. Future research directions include understanding when, where, and how formate is used and produced by these organisms in nature, and how transcription of Thermococci genes encoding formate-related enzymes are regulated.
Collapse
|
11
|
Boyd ES, Spietz RL, Kour M, Colman DR. A naturalist perspective of microbiology: Examples from methanogenic archaea. Environ Microbiol 2023; 25:184-198. [PMID: 36367391 DOI: 10.1111/1462-2920.16285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2022] [Accepted: 11/09/2022] [Indexed: 11/13/2022]
Abstract
Storytelling has been the primary means of knowledge transfer over human history. The effectiveness and reach of stories are improved when the message is appropriate for the target audience. Oftentimes, the stories that are most well received and recounted are those that have a clear purpose and that are told from a variety of perspectives that touch on the varied interests of the target audience. Whether scientists realize or not, they are accustomed to telling stories of their own scientific discoveries through the preparation of manuscripts, presentations, and lectures. Perhaps less frequently, scientists prepare review articles or book chapters that summarize a body of knowledge on a given subject matter, meant to be more holistic recounts of a body of literature. Yet, by necessity, such summaries are often still narrow in their scope and are told from the perspective of a particular discipline. In other words, interdisciplinary reviews or book chapters tend to be the rarity rather than the norm. Here, we advocate for and highlight the benefits of interdisciplinary perspectives on microbiological subjects.
Collapse
Affiliation(s)
- Eric S Boyd
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, Montana, USA
| | - Rachel L Spietz
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, Montana, USA
| | - Manjinder Kour
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, Montana, USA
| | - Daniel R Colman
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, Montana, USA
| |
Collapse
|
12
|
Narrowing gaps between Earth and life. Proc Natl Acad Sci U S A 2022; 119:e2216017119. [PMID: 36288265 PMCID: PMC9674954 DOI: 10.1073/pnas.2216017119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
|