{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,8]],"date-time":"2026-07-08T15:17:54Z","timestamp":1783523874212,"version":"3.55.0"},"reference-count":173,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2026,7,8]],"date-time":"2026-07-08T00:00:00Z","timestamp":1783468800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"NASA Astrobiology: Exobiology and Evolutionary Biology Program","award":["#NNX12AD90G"],"award-info":[{"award-number":["#NNX12AD90G"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Over the course of Martian history, the presence of atmospheric carbon dioxide and potential subsurface molecular hydrogen (H2), in addition to potential surface and subsurface liquid water, suggests that the Martian subsurface, at minimum, may once have been habitable, particularly to autotrophic chemosynthetic microorganisms. In addition, the widespread nature of clays and other minerals on Mars could have provided sufficient nutrients to support microbial life. Here we tested four methanogenic species (Methanosarcina barkeri, Methanobacterium formicicum, Methanothermobacter wolfeii, and Methanococcus maripaludis) in the presence of illite, nontronite, and Mojave Mars Simulant (MMS), in their standard growth medium. We aimed to determine whether the presence of certain Mars simulants inhibited, promoted, or had no effect on methane (CH4) production by these microorganisms. The same methanogens were also tested in the presence of montmorillonite, H2, sodium sulfide (Na2S), and bicarbonate buffer to determine if this clay could support biotic CH4 production. Three of the four methanogens tested (M. barkeri, M. formicicum, and M. wolfeii) were capable of CH4 production in the presence of both clay minerals and MMS, as well as in cultures containing only 10% (w\/v) montmorillonite, H2, Na2S, and bicarbonate buffer. Conversely, M. maripaludis, a halophile, showed the greatest sensitivity of the four methanogens tested; however, the presence of 5% (w\/v) montmorillonite enabled greater CH4 production under certain circumstances compared to cultures containing the organism\u2019s standard growth medium alone. Overall, these results suggest that the presence of clay minerals on Mars does not preclude the survivability and growth of methanogens in a potential subsurface habitat. In fact, these geological components may provide sufficient nutrients to support microbial growth and survivability.<\/jats:p>","DOI":"10.3390\/microorganisms14071496","type":"journal-article","created":{"date-parts":[[2026,7,8]],"date-time":"2026-07-08T14:27:23Z","timestamp":1783520843000},"page":"1496","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Methane Production on Mars-Relevant Clay Minerals and Simulant Regolith"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4493-7263","authenticated-orcid":false,"given":"Rebecca L.","family":"Mickol","sequence":"first","affiliation":[{"name":"US Naval Research Laboratory, 4555 Overlook Ave SW, Washington, DC 20375, USA"},{"name":"Arkansas Center for Space and Planetary Science, University of Arkansas, 332 N. Arkansas Ave, Fayetteville, AR 72701, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"William Hunter","family":"Waddell","sequence":"additional","affiliation":[{"name":"Department of Biological Sciences, University of Arkansas, Science and Engineering Room 601, Fayetteville, AR 72701, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"James","family":"Wray","sequence":"additional","affiliation":[{"name":"Department of Biological Sciences, University of Arkansas, Science and Engineering Room 601, Fayetteville, AR 72701, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ryan","family":"Pohlkamp","sequence":"additional","affiliation":[{"name":"Department of Biological Sciences, University of Arkansas, Science and Engineering Room 601, Fayetteville, AR 72701, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chandler","family":"Kern","sequence":"additional","affiliation":[{"name":"Department of Biological Sciences, University of Arkansas, Science and Engineering Room 601, Fayetteville, AR 72701, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Timothy A.","family":"Kral","sequence":"additional","affiliation":[{"name":"Arkansas Center for Space and Planetary Science, University of Arkansas, 332 N. Arkansas Ave, Fayetteville, AR 72701, USA"},{"name":"Department of Biological Sciences, University of Arkansas, Science and Engineering Room 601, Fayetteville, AR 72701, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"415","DOI":"10.1126\/science.1261713","article-title":"Mars methane detection and variability at Gale crater","volume":"347","author":"Webster","year":"2015","journal-title":"Science"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1093","DOI":"10.1126\/science.aaq0131","article-title":"Background levels of methane in Mars\u2019 atmosphere show strong seasonal variations","volume":"360","author":"Webster","year":"2018","journal-title":"Science"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"A166","DOI":"10.1051\/0004-6361\/202040030","article-title":"Day-night differences in Mars methane suggest nighttime containment at Gale crater","volume":"650","author":"Webster","year":"2021","journal-title":"Astron. Astrophys."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1041","DOI":"10.1126\/science.1165243","article-title":"Strong release of methane on Mars in northern summer 2003","volume":"323","author":"Mumma","year":"2009","journal-title":"Science"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1758","DOI":"10.1126\/science.1101732","article-title":"Detection of methane in the atmosphere of Mars","volume":"306","author":"Formisano","year":"2004","journal-title":"Science"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"1194","DOI":"10.1016\/j.pss.2008.03.004","article-title":"Methane in Martian atmosphere: Average spatial, diurnal, and seasonal behaviour","volume":"56","author":"Geminale","year":"2008","journal-title":"Planet. Space Sci."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"137","DOI":"10.1016\/j.pss.2010.07.011","article-title":"Mapping methane in Martian atmosphere with PFS-MEX data","volume":"59","author":"Geminale","year":"2011","journal-title":"Planet. Space Sci."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"326","DOI":"10.1038\/s41561-019-0331-9","article-title":"Independent confirmation of a methane spike on Mars and a source region east of Gale Crater","volume":"12","author":"Giuranna","year":"2019","journal-title":"Nat. Geosci."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"A51","DOI":"10.1051\/0004-6361\/200913178","article-title":"Mapping the methane on Mars","volume":"512","author":"Fonti","year":"2010","journal-title":"Astron. Astrophys."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"e2115651119","DOI":"10.1073\/pnas.2115651119","article-title":"Depleted carbon isotope compositions observed at Gale crater, Mars","volume":"119","author":"House","year":"2022","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"6525","DOI":"10.1029\/96JE03766","article-title":"High-resolution spectroscopy of Mars at 3.7 and 8 \u03bcm: A sensitive search for H2O2, H2CO, HCl, and CH4, and detection of HDO","volume":"102","author":"Krasnopolsky","year":"1997","journal-title":"J. Geophys. Res. Planets"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"537","DOI":"10.1016\/j.icarus.2004.07.004","article-title":"Detection of methane in the martian atmosphere: Evidence for life?","volume":"172","author":"Krasnopolsky","year":"2004","journal-title":"Icarus"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"A140","DOI":"10.1051\/0004-6361\/202140389","article-title":"A stringent upper limit of 20 pptv for methane on Mars and constraints on its dispersion outside Gale crater","volume":"650","author":"Montmessin","year":"2021","journal-title":"Astron. Astrophys."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"A78","DOI":"10.1051\/0004-6361\/201730903","article-title":"Stringent upper limit of CH4 on Mars based on SOFIA\/EXES observations","volume":"610","author":"Aoki","year":"2018","journal-title":"Astron. Astrophys."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"355","DOI":"10.1126\/science.1242902","article-title":"Low upper limit to methane abundance on Mars","volume":"342","author":"Webster","year":"2013","journal-title":"Science"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"A136","DOI":"10.1051\/0004-6361\/201526235","article-title":"Revisiting the identification of methane on Mars using TES data","volume":"581","author":"Fonti","year":"2015","journal-title":"Astron. Astrophys."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"113407","DOI":"10.1016\/j.icarus.2019.113407","article-title":"Statistical analysis of Curiosity data shows no evidence for a strong seasonal cycle of Martian methane","volume":"336","author":"Gillen","year":"2020","journal-title":"Icarus"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"114266","DOI":"10.1016\/j.icarus.2020.114266","article-title":"Comprehensive investigation of Mars methane and organics with ExoMars\/NOMAD","volume":"357","author":"Knutsen","year":"2021","journal-title":"Icarus"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"11","DOI":"10.1016\/j.icarus.2012.11.013","article-title":"A sensitive search for organics (CH4, CH3OH, H2CO, C2H6, C2H2, C2H4), hydroperoxyl (HO2), nitrogen compounds (N2O, NH3, HCN) and chlorine species (HCl, CH3Cl) on Mars using ground-based high-resolution infrared spectroscopy","volume":"223","author":"Villanueva","year":"2013","journal-title":"Icarus"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"144","DOI":"10.1016\/j.icarus.2011.10.019","article-title":"Search for methane and upper limits to ethane and SO2 on Mars","volume":"217","author":"Krasnopolsky","year":"2012","journal-title":"Icarus"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"1263","DOI":"10.1038\/s41550-022-01786-w","article-title":"Early Mars habitability and global cooling by H2-based methanogens","volume":"6","author":"Sauterey","year":"2022","journal-title":"Nat. Astron."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"253","DOI":"10.1089\/ast.2024.0100","article-title":"Potential Habitability of Present-Day Martian Subsurface for Earth-Like Methanogens","volume":"25","author":"Butturini","year":"2025","journal-title":"Astrobiology"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"337","DOI":"10.1080\/10409238.2024.2418639","article-title":"Methanogens and what they tell us about how life might survive on Mars","volume":"59","author":"Paulchamy","year":"2024","journal-title":"Crit. Rev. Biochem. Mol. Biol."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"1775","DOI":"10.1016\/j.pss.2010.08.014","article-title":"The chemical biology of methanogenesis","volume":"58","author":"Ferry","year":"2010","journal-title":"Planet. Space Sci."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"312","DOI":"10.1038\/415312a","article-title":"A hydrogen-based subsurface microbial community dominated by methanogens","volume":"415","author":"Chapelle","year":"2002","journal-title":"Nature"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"300","DOI":"10.1016\/0019-1035(92)90045-9","article-title":"On the possibility of chemosynthetic ecosystems in subsurface habitats on Mars","volume":"95","author":"Boston","year":"1992","journal-title":"Icarus"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"311","DOI":"10.1023\/A:1006552412928","article-title":"Hydrogen consumption by methanogens on the early Earth","volume":"28","author":"Kral","year":"1998","journal-title":"Orig. Life Evol. Biosph."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"4165","DOI":"10.1029\/1999JE001119","article-title":"The state, potential distribution, and biological implications of methane in the Martian crust","volume":"105","author":"Max","year":"2000","journal-title":"J. Geophys. Res. Planets"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"7399","DOI":"10.1038\/ncomms8399","article-title":"Evidence for methane in Martian meteorites","volume":"6","author":"Blamey","year":"2015","journal-title":"Nat. Commun."},{"key":"ref_30","doi-asserted-by":"crossref","unstructured":"Crawford, R.L., and Newcombe, D.A. (2008). The potential for extant life in the soils of Mars. Microbiology of Extreme Soils, Springer.","DOI":"10.1007\/978-3-540-74231-9_11"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"1.13","DOI":"10.1093\/astrogeo\/ats034","article-title":"Plausible microbial metabolisms on Mars","volume":"54","author":"Nixon","year":"2013","journal-title":"Astron. Geophys."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"431","DOI":"10.1089\/ast.2022.0064","article-title":"Quantifying the bioavailable energy in an ancient hydrothermal vent on Mars and a modern Earth-based analog","volume":"23","author":"Rucker","year":"2023","journal-title":"Astrobiology"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"23687","DOI":"10.1029\/97JE01087","article-title":"High-temperature life without photosynthesis as a model for Mars","volume":"102","author":"Shock","year":"1997","journal-title":"J. Geophys. Res. Planets"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"215","DOI":"10.1016\/S0273-1177(99)80087-8","article-title":"Biogeochemical evidence of microbial activity on Mars","volume":"15","author":"Ivanov","year":"1995","journal-title":"Adv. Space Res."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"1652","DOI":"10.3390\/life5041652","article-title":"Assessing the ecophysiology of methanogens in the context of recent astrobiological and planetological studies","volume":"5","author":"Taubner","year":"2015","journal-title":"Life"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"e2022GL098946","DOI":"10.1029\/2022GL098946","article-title":"Barometric pumping through fractured rock: A mechanism for venting deep methane to Mars\u2019 atmosphere","volume":"49","author":"Ortiz","year":"2022","journal-title":"Geophys. Res. Lett."},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Hart, R., and Cardace, D. (2023). Mineral Indicators of Geologically Recent Past Habitability on Mars. Life, 13.","DOI":"10.3390\/life13122349"},{"key":"ref_38","doi-asserted-by":"crossref","unstructured":"Nisson, D.M., Mickol, R.L., Robinson, A., and Lloyd, K. (2026). Life Detection in the Martian Subsurface: Advancements in Microbial Metabolic Research Under Martian Laboratory and Field Analog Conditions since Viking. Astrobiology.","DOI":"10.1177\/15311074261464014"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"377","DOI":"10.1089\/ast.2006.6.377","article-title":"Martian CH4: Sources, flux, and detection","volume":"6","author":"Onstott","year":"2006","journal-title":"Astrobiology"},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"971","DOI":"10.1089\/ast.2006.0096","article-title":"Hydrogeologic controls on episodic H2 release from Precambrian fractured rocks\u2014Energy for deep subsurface life on Earth and Mars","volume":"7","author":"Voglesonger","year":"2007","journal-title":"Astrobiology"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"L06201","DOI":"10.1029\/2010GL042596","article-title":"Geologic setting of serpentine deposits on Mars","volume":"37","author":"Ehlmann","year":"2010","journal-title":"Geophys. Res. Lett."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"690","DOI":"10.1089\/ast.2015.1405","article-title":"Evidence for seismogenic hydrogen gas, a potential microbial energy source on Earth and Mars","volume":"16","author":"McMahon","year":"2016","journal-title":"Astrobiology"},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"1137","DOI":"10.1089\/ast.2017.1654","article-title":"Radiolytic H2 production in martian environments","volume":"18","author":"Dzaugis","year":"2018","journal-title":"Astrobiology"},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"655","DOI":"10.1089\/ast.2018.1835","article-title":"A maximum subsurface biomass on Mars from untapped free energy: CO and H2 as potential antibiosignatures","volume":"19","author":"Sholes","year":"2019","journal-title":"Astrobiology"},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"11646","DOI":"10.1038\/s41598-020-68715-7","article-title":"Investigating the biological potential of galactic cosmic ray-induced radiation-driven chemical disequilibrium in the Martian subsurface environment","volume":"10","author":"Atri","year":"2020","journal-title":"Sci. Rep."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"133","DOI":"10.1016\/j.epsl.2018.09.001","article-title":"Radiolytic H2 production on Noachian Mars: Implications for habitability and atmospheric warming","volume":"502","author":"Tarnas","year":"2018","journal-title":"Earth Planet. Sci. Lett."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"212","DOI":"10.1126\/science.1220715","article-title":"A reduced organic carbon component in martian basalts","volume":"337","author":"Steele","year":"2012","journal-title":"Science"},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"495","DOI":"10.1002\/2014JE004737","article-title":"Organic molecules in the Sheepbed Mudstone, Gale Crater, Mars","volume":"120","author":"Freissinet","year":"2015","journal-title":"J. Geophys. Res. Planets"},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"1096","DOI":"10.1126\/science.aas9185","article-title":"Organic matter preserved in 3-billion-year-old mudstones at Gale crater, Mars","volume":"360","author":"Eigenbrode","year":"2018","journal-title":"Science"},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"e2201139119","DOI":"10.1073\/pnas.2201139119","article-title":"Organic carbon concentrations in 3.5-billion-year-old lacustrine mudstones of Mars","volume":"119","author":"Stern","year":"2022","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_51","doi-asserted-by":"crossref","unstructured":"Ansari, A.H. (2023). Detection of organic matter on Mars, results from various Mars missions, challenges, and future strategy: A review. Front. Astron. Space Sci., 10.","DOI":"10.3389\/fspas.2023.1075052"},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"400","DOI":"10.1126\/science.1122659","article-title":"Global mineralogical and aqueous Mars history derived from OMEGA\/Mars Express data","volume":"312","author":"Bibring","year":"2006","journal-title":"Science"},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"373","DOI":"10.1016\/j.icarus.2014.11.011","article-title":"Widespread surface weathering on early Mars: A case for a warmer and wetter climate","volume":"248","author":"Carter","year":"2015","journal-title":"Icarus"},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"2118","DOI":"10.1021\/acsearthspacechem.2c00091","article-title":"Enigmatic Issues and Widening Implications of Research on Martian Clay Minerals","volume":"6","author":"Zhong","year":"2022","journal-title":"ACS Earth Space Chem."},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"L04201","DOI":"10.1029\/2009GL041870","article-title":"Paleoclimate of Mars as captured by the stratigraphic record in Gale Crater","volume":"37","author":"Milliken","year":"2010","journal-title":"Geophys. Res. Lett."},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"125605","DOI":"10.1016\/j.chemer.2020.125605","article-title":"Mineralogy and geochemistry of sedimentary rocks and eolian sediments in Gale crater, Mars: A review after six Earth years of exploration with Curiosity","volume":"80","author":"Rampe","year":"2020","journal-title":"Geochemistry"},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"115114","DOI":"10.1016\/j.icarus.2022.115114","article-title":"Constraining the spectral behavior of the clay-bearing outcrops in Oxia Planum, the landing site for ExoMars \u201cRosalind Franklin\u201d rover","volume":"386","author":"Brossier","year":"2022","journal-title":"Icarus"},{"key":"ref_58","doi-asserted-by":"crossref","first-page":"27","DOI":"10.3847\/PSJ\/acb3bc","article-title":"Spectral Analysis of Clay-bearing Outcrops in Northern Xanthe Terra, Mars: Comparison with Oxia Planum, the Landing Site for the ExoMars Rover Mission","volume":"4","author":"Brossier","year":"2023","journal-title":"Planet. Sci. J."},{"key":"ref_59","doi-asserted-by":"crossref","first-page":"e2021JE007098","DOI":"10.1029\/2021JE007098","article-title":"The distribution of clay minerals and their impact on diagenesis in Glen Torridon, Gale crater, Mars","volume":"127","author":"Rudolph","year":"2022","journal-title":"J. Geophys. Res. Planets"},{"key":"ref_60","doi-asserted-by":"crossref","first-page":"623","DOI":"10.1038\/nature04274","article-title":"Phyllosilicates on Mars and implications for early Martian climate","volume":"438","author":"Poulet","year":"2005","journal-title":"Nature"},{"key":"ref_61","doi-asserted-by":"crossref","first-page":"L41","DOI":"10.1051\/0004-6361:200810150","article-title":"Abundance of minerals in the phyllosilicate-rich units on Mars","volume":"487","author":"Poulet","year":"2008","journal-title":"Astron. Astrophys."},{"key":"ref_62","doi-asserted-by":"crossref","first-page":"E06S01","DOI":"10.1029\/2006JE002756","article-title":"Evidence for montmorillonite or its compositional equivalent in Columbia Hills, Mars","volume":"112","author":"Clark","year":"2007","journal-title":"J. Geophys. Res. Planets"},{"key":"ref_63","doi-asserted-by":"crossref","first-page":"35","DOI":"10.1180\/claymin.2008.043.1.03","article-title":"Reflectance and emission spectroscopy study of four groups of phyllosilicates: Smectites, kaolinite-serpentines, chlorites and micas","volume":"43","author":"Bishop","year":"2008","journal-title":"Clay Miner."},{"key":"ref_64","doi-asserted-by":"crossref","first-page":"830","DOI":"10.1126\/science.1159699","article-title":"Phyllosilicate diversity and past aqueous activity revealed at Mawrth Vallis, Mars","volume":"321","author":"Bishop","year":"2008","journal-title":"Science"},{"key":"ref_65","doi-asserted-by":"crossref","first-page":"305","DOI":"10.1038\/nature07097","article-title":"Hydrated silicate minerals on Mars observed by the Mars Reconnaissance Orbiter CRISM instrument","volume":"454","author":"Mustard","year":"2008","journal-title":"Nature"},{"key":"ref_66","doi-asserted-by":"crossref","first-page":"L12202","DOI":"10.1029\/2008GL034385","article-title":"Compositional stratigraphy of clay-bearing layered deposits at Mawrth Vallis, Mars","volume":"35","author":"Wray","year":"2008","journal-title":"Geophys. Res. Lett."},{"key":"ref_67","doi-asserted-by":"crossref","first-page":"E00D06","DOI":"10.1029\/2009JE003342","article-title":"A synthesis of Martian aqueous mineralogy after 1 Mars year of observations from the Mars Reconnaissance Orbiter","volume":"114","author":"Murchie","year":"2009","journal-title":"J. Geophys. Res. Planets"},{"key":"ref_68","doi-asserted-by":"crossref","first-page":"53","DOI":"10.1038\/nature10582","article-title":"Subsurface water and clay mineral formation during the early history of Mars","volume":"479","author":"Ehlmann","year":"2011","journal-title":"Nature"},{"key":"ref_69","doi-asserted-by":"crossref","first-page":"130","DOI":"10.1016\/j.pss.2013.05.006","article-title":"What the ancient phyllosilicates at Mawrth Vallis can tell us about possible habitability on early Mars","volume":"86","author":"Bishop","year":"2013","journal-title":"Planet. Space Sci."},{"key":"ref_70","doi-asserted-by":"crossref","first-page":"104491","DOI":"10.1016\/j.earscirev.2023.104491","article-title":"Clay minerals on Mars: An up-to-date review with future perspectives","volume":"243","author":"Du","year":"2023","journal-title":"Earth-Sci. Rev."},{"key":"ref_71","doi-asserted-by":"crossref","first-page":"105924","DOI":"10.1016\/j.pss.2024.105924","article-title":"Clay mineralogy in west Chryse Planitia, Mars: Comparison with present and future landing sites","volume":"247","author":"Brossier","year":"2024","journal-title":"Planet. Space Sci."},{"key":"ref_72","doi-asserted-by":"crossref","first-page":"116538","DOI":"10.1016\/j.icarus.2025.116538","article-title":"The mineralogical composition of Jezero Crater Western Fan: Multigaussian modeling of Perseverance\/SuperCam near-infrared observations and overview of major units","volume":"434","author":"Royer","year":"2025","journal-title":"Icarus"},{"key":"ref_73","doi-asserted-by":"crossref","unstructured":"Tu, V.M., Rampe, E.B., Bristow, T.F., Thorpe, M.T., Clark, J.V., Castle, N., Fraeman, A.A., Edgar, L.A., McAdam, A., and Bedford, C. (2021). A review of the phyllosilicates in Gale Crater as detected by the CheMin instrument on the Mars Science Laboratory, Curiosity rover. Minerals, 11.","DOI":"10.3390\/min11080847"},{"key":"ref_74","doi-asserted-by":"crossref","first-page":"e2019JE006351","DOI":"10.1029\/2019JE006351","article-title":"Martian hydrated minerals: A significant water sink","volume":"126","author":"Wernicke","year":"2021","journal-title":"J. Geophys. Res. Planets"},{"key":"ref_75","doi-asserted-by":"crossref","first-page":"e2023JE008159","DOI":"10.1029\/2023JE008159","article-title":"Fate of an earth-like water inventory on Mars","volume":"129","author":"Jakosky","year":"2024","journal-title":"J. Geophys. Res. Planets"},{"key":"ref_76","doi-asserted-by":"crossref","first-page":"1242777","DOI":"10.1126\/science.1242777","article-title":"A habitable fluvio-lacustrine environment at Yellowknife Bay, Gale Crater, Mars","volume":"343","author":"Grotzinger","year":"2014","journal-title":"Science"},{"key":"ref_77","doi-asserted-by":"crossref","first-page":"11805","DOI":"10.1029\/1999JE900010","article-title":"Sources of nutrients and energy for a deep biosphere on Mars","volume":"104","author":"Fisk","year":"1999","journal-title":"J. Geophys. Res. Planets"},{"key":"ref_78","doi-asserted-by":"crossref","first-page":"1249","DOI":"10.1098\/rstb.2004.1502","article-title":"Life at low water activity","volume":"359","author":"Grant","year":"2004","journal-title":"Philos. Trans. R. Soc. Lond. B Biol. Sci."},{"key":"ref_79","doi-asserted-by":"crossref","first-page":"1204","DOI":"10.1126\/science.1155432","article-title":"Water activity and the challenge for life on early Mars","volume":"320","author":"Tosca","year":"2008","journal-title":"Science"},{"key":"ref_80","doi-asserted-by":"crossref","first-page":"91","DOI":"10.1016\/j.clay.2019.04.025","article-title":"Interactions between microorganisms and clay minerals: New insights and broader applications","volume":"177","author":"Li","year":"2019","journal-title":"Appl. Clay Sci."},{"key":"ref_81","doi-asserted-by":"crossref","first-page":"381","DOI":"10.1111\/j.1574-6941.2008.00645.x","article-title":"Minerals in soil select distinct bacterial communities in their microhabitats","volume":"67","author":"Carson","year":"2009","journal-title":"FEMS Microbiol. Ecol."},{"key":"ref_82","doi-asserted-by":"crossref","first-page":"35","DOI":"10.1016\/j.chemgeo.2011.11.003","article-title":"Microbial reduction of Fe (III) in illite\u2013smectite minerals by methanogen Methanosarcina mazei","volume":"292","author":"Zhang","year":"2012","journal-title":"Chem. Geol."},{"key":"ref_83","doi-asserted-by":"crossref","first-page":"203","DOI":"10.1016\/j.gca.2012.12.031","article-title":"Microbial reduction of Fe (III) in smectite minerals by thermophilic methanogen Methanothermobacter thermautotrophicus","volume":"106","author":"Zhang","year":"2013","journal-title":"Geochim. Cosmochim. Acta"},{"key":"ref_84","doi-asserted-by":"crossref","first-page":"E02S19","DOI":"10.1029\/2005JE002515","article-title":"In situ and experimental evidence for acidic weathering of rocks and soils on Mars","volume":"111","author":"Hurowitz","year":"2006","journal-title":"J. Geophys. Res. Planets"},{"key":"ref_85","doi-asserted-by":"crossref","first-page":"432","DOI":"10.1016\/j.epsl.2007.05.043","article-title":"A \u223c3.5 Ga record of water-limited, acidic weathering conditions on Mars","volume":"260","author":"Hurowitz","year":"2007","journal-title":"Earth Planet. Sci. Lett."},{"key":"ref_86","doi-asserted-by":"crossref","first-page":"6232","DOI":"10.1016\/j.gca.2010.08.005","article-title":"Mineralogical characterization of acid weathered phyllosilicates with implications for secondary Martian deposits","volume":"74","author":"Altheide","year":"2010","journal-title":"Geochim. Cosmochim. Acta"},{"key":"ref_87","doi-asserted-by":"crossref","first-page":"248","DOI":"10.1016\/j.gca.2017.10.004","article-title":"Smectite formation in the presence of sulfuric acid: Implications for acidic smectite formation on early Mars","volume":"220","author":"Peretyazhko","year":"2018","journal-title":"Geochim. Cosmochim. Acta"},{"key":"ref_88","doi-asserted-by":"crossref","first-page":"37","DOI":"10.1016\/j.gca.2015.10.012","article-title":"Fe\/Mg smectite formation under acidic conditions on early Mars","volume":"173","author":"Peretyazhko","year":"2016","journal-title":"Geochim. Cosmochim. Acta"},{"key":"ref_89","doi-asserted-by":"crossref","first-page":"116016","DOI":"10.1016\/j.icarus.2024.116016","article-title":"Experimental transformation of nontronite to kaolinite: Implication for ferrallitization of Fe\/Mg-rich clays in compositional stratigraphy on Mars","volume":"413","author":"Qin","year":"2024","journal-title":"Icarus"},{"key":"ref_90","doi-asserted-by":"crossref","first-page":"266","DOI":"10.1038\/s43247-022-00602-7","article-title":"Chemical weathering over hundreds of millions of years of greenhouse conditions on Mars","volume":"3","author":"Ye","year":"2022","journal-title":"Commun. Earth Environ."},{"key":"ref_91","doi-asserted-by":"crossref","first-page":"503","DOI":"10.1038\/s41550-021-01303-5","article-title":"Anoxic chemical weathering under a reducing greenhouse on early Mars","volume":"5","author":"Liu","year":"2021","journal-title":"Nat. Astron."},{"key":"ref_92","doi-asserted-by":"crossref","first-page":"409","DOI":"10.1130\/G52988.1","article-title":"Topography and mineralogy of clay deposits signify an epoch of warm and humid climate on early Mars","volume":"53","author":"Klidaras","year":"2025","journal-title":"Geology"},{"key":"ref_93","doi-asserted-by":"crossref","unstructured":"Saumya, T., and Wray, J.J. (2026). The interplay between magmatic and sedimentary processes on Noachian Mars and its implications for habitability. Front. Astron. Space Sci., 13.","DOI":"10.3389\/fspas.2026.1695941"},{"key":"ref_94","doi-asserted-by":"crossref","first-page":"E00D08","DOI":"10.1029\/2009JE003339","article-title":"Identification of hydrated silicate minerals on Mars using MRO-CRISM: Geologic context near Nili Fossae and implications for aqueous alteration","volume":"114","author":"Ehlmann","year":"2009","journal-title":"J. Geophys. Res. Planets"},{"key":"ref_95","doi-asserted-by":"crossref","first-page":"936","DOI":"10.1038\/s41550-021-01397-x","article-title":"Long-lasting habitable periods in Gale crater constrained by glauconitic clays","volume":"5","author":"Bishop","year":"2021","journal-title":"Nat. Astron."},{"key":"ref_96","doi-asserted-by":"crossref","first-page":"725","DOI":"10.1130\/0016-7606(1976)87<725:MOBMOA>2.0.CO;2","article-title":"Mechanism of burial metamorphism of argillaceous sediment: 1. Mineralogical and chemical evidence","volume":"87","author":"Hower","year":"1976","journal-title":"Geol. Soc. Am. Bull."},{"key":"ref_97","doi-asserted-by":"crossref","first-page":"25","DOI":"10.1016\/j.clay.2013.09.009","article-title":"High-pressure adsorption of methane on montmorillonite, kaolinite and illite","volume":"85","author":"Liu","year":"2013","journal-title":"Appl. Clay Sci."},{"key":"ref_98","doi-asserted-by":"crossref","first-page":"1243480","DOI":"10.1126\/science.1243480","article-title":"Mineralogy of a mudstone at Yellowknife Bay, Gale crater, Mars","volume":"343","author":"Vaniman","year":"2014","journal-title":"Science"},{"key":"ref_99","doi-asserted-by":"crossref","first-page":"172","DOI":"10.1016\/j.epsl.2017.04.021","article-title":"Mineralogy of an ancient lacustrine mudstone succession from the Murray formation, Gale crater, Mars","volume":"471","author":"Rampe","year":"2017","journal-title":"Earth Planet. Sci. Lett."},{"key":"ref_100","doi-asserted-by":"crossref","first-page":"eaar3330","DOI":"10.1126\/sciadv.aar3330","article-title":"Clay mineral diversity and abundance in sedimentary rocks of Gale crater, Mars","volume":"4","author":"Bristow","year":"2018","journal-title":"Sci. Adv."},{"key":"ref_101","doi-asserted-by":"crossref","first-page":"777","DOI":"10.1016\/S0045-6535(02)00380-6","article-title":"Geologic emissions of methane to the atmosphere","volume":"49","author":"Etiope","year":"2002","journal-title":"Chemosphere"},{"key":"ref_102","doi-asserted-by":"crossref","first-page":"629","DOI":"10.1042\/ETLS20180031","article-title":"Methanogens: Pushing the boundaries of biology","volume":"2","author":"Buan","year":"2018","journal-title":"Emerg. Top. Life Sci."},{"key":"ref_103","doi-asserted-by":"crossref","first-page":"89","DOI":"10.1017\/S1473550406002916","article-title":"Terrestrial models for extraterrestrial life: Methanogens and halophiles at Martian temperatures","volume":"5","author":"Reid","year":"2006","journal-title":"Int. J. Astrobiol."},{"key":"ref_104","doi-asserted-by":"crossref","first-page":"16","DOI":"10.1111\/j.1574-6941.2007.00316.x","article-title":"Stress response of methanogenic archaea from Siberian permafrost compared with methanogens from nonpermafrost habitats","volume":"61","author":"Morozova","year":"2007","journal-title":"FEMS Microbiol. Ecol."},{"key":"ref_105","doi-asserted-by":"crossref","first-page":"615","DOI":"10.1023\/B:ORIG.0000043129.68196.5f","article-title":"Growth of methanogens on a Mars soil simulant","volume":"34","author":"Kral","year":"2004","journal-title":"Orig. Life Evol. Biosph."},{"key":"ref_106","doi-asserted-by":"crossref","first-page":"546","DOI":"10.1089\/ast.2006.6.546","article-title":"Survival of methanogens during desiccation: Implications for life on Mars","volume":"6","author":"Kendrick","year":"2006","journal-title":"Astrobiology"},{"key":"ref_107","doi-asserted-by":"crossref","first-page":"343","DOI":"10.1006\/icar.2000.6393","article-title":"The ultraviolet environment of Mars: Biological implications past, present, and future","volume":"146","author":"Cockell","year":"2000","journal-title":"Icarus"},{"key":"ref_108","doi-asserted-by":"crossref","first-page":"1244797","DOI":"10.1126\/science.1244797","article-title":"Mars\u2019 surface radiation environment measured with the Mars Science Laboratory\u2019s Curiosity rover","volume":"343","author":"Hassler","year":"2014","journal-title":"Science"},{"key":"ref_109","doi-asserted-by":"crossref","first-page":"357","DOI":"10.1038\/ngeo2412","article-title":"Transient liquid water and water activity at Gale crater on Mars","volume":"8","author":"Zorzano","year":"2015","journal-title":"Nat. Geosci."},{"key":"ref_110","doi-asserted-by":"crossref","first-page":"28545","DOI":"10.1029\/98JE02081","article-title":"Surviving the limits to life at the surface of Mars","volume":"103","author":"Clark","year":"1998","journal-title":"J. Geophys. Res. Planets"},{"key":"ref_111","doi-asserted-by":"crossref","first-page":"E00E20","DOI":"10.1029\/2009JE003421","article-title":"Habitability of the Phoenix landing site","volume":"115","author":"Stoker","year":"2010","journal-title":"J. Geophys. Res. Planets"},{"key":"ref_112","doi-asserted-by":"crossref","first-page":"91","DOI":"10.1016\/j.pss.2012.07.026","article-title":"Biotoxicity of Mars soils: 1. Dry deposition of analog soils on microbial colonies and survival under Martian conditions","volume":"72","author":"Schuerger","year":"2012","journal-title":"Planet. Space Sci."},{"key":"ref_113","doi-asserted-by":"crossref","first-page":"358","DOI":"10.1016\/j.pss.2006.02.005","article-title":"Methane and related trace species on Mars: Origin, loss, implications for life, and habitability","volume":"55","author":"Atreya","year":"2007","journal-title":"Planet. Space Sci."},{"key":"ref_114","doi-asserted-by":"crossref","first-page":"133","DOI":"10.1016\/j.pss.2010.10.008","article-title":"Methane on Mars: Current observations, interpretation, and future plans","volume":"59","author":"Atreya","year":"2011","journal-title":"Planet. Space Sci."},{"key":"ref_115","doi-asserted-by":"crossref","first-page":"511","DOI":"10.1007\/s11084-016-9519-9","article-title":"Low pressure tolerance by methanogens in an aqueous environment: Implications for subsurface life on Mars","volume":"47","author":"Mickol","year":"2017","journal-title":"Orig. Life Evol. Biosph."},{"key":"ref_116","doi-asserted-by":"crossref","first-page":"79","DOI":"10.1016\/j.pss.2017.12.014","article-title":"Low pressure microenvironments: Methane production at 50 mbar and 100 mbar by methanogens","volume":"153","author":"Mickol","year":"2018","journal-title":"Planet. Space Sci."},{"key":"ref_117","doi-asserted-by":"crossref","first-page":"15","DOI":"10.1016\/j.pss.2016.11.012","article-title":"Survivability and growth kinetics of methanogenic archaea at various pHs and pressures: Implications for deep subsurface life on Mars","volume":"136","author":"Sinha","year":"2017","journal-title":"Planet. Space Sci."},{"key":"ref_118","doi-asserted-by":"crossref","first-page":"179","DOI":"10.1017\/S1473550418000216","article-title":"Effects of temperatures and high pressures on the growth and survivability of methanogens and stable carbon isotope fractionation: Implications for deep subsurface life on Mars","volume":"20","author":"Sinha","year":"2021","journal-title":"Int. J. Astrobiol."},{"key":"ref_119","doi-asserted-by":"crossref","unstructured":"Checinska Sielaff, A., and Smith, S.A. (2019). Habitability of Mars: How welcoming are the surface and subsurface to life on the red planet?. Geosciences, 9.","DOI":"10.3390\/geosciences9090361"},{"key":"ref_120","doi-asserted-by":"crossref","first-page":"2880","DOI":"10.1038\/s41598-025-86145-1","article-title":"Hydrogenotrophic methanogenesis at 7\u201312 mbar by Methanosarcina barkeri under simulated Martian atmospheric conditions","volume":"15","author":"Harris","year":"2025","journal-title":"Sci. Rep."},{"key":"ref_121","doi-asserted-by":"crossref","unstructured":"Schirmack, J., Alawi, M., and Wagner, D. (2015). Influence of Martian regolith analogs on the activity and growth of methanogenic archaea, with special regard to long-term desiccation. Front. Microbiol., 6.","DOI":"10.3389\/fmicb.2015.00210"},{"key":"ref_122","doi-asserted-by":"crossref","first-page":"35","DOI":"10.1016\/j.pss.2015.04.011","article-title":"Stable carbon isotope fractionation by methanogens growing on different Mars regolith analogs","volume":"112","author":"Sinha","year":"2015","journal-title":"Planet. Space Sci."},{"key":"ref_123","doi-asserted-by":"crossref","first-page":"889","DOI":"10.1089\/ast.2010.0480","article-title":"Approaching Mars-like geochemical conditions in the laboratory: Omission of artificial buffers and reductants in a study of biogenic methane production on a smectite clay","volume":"10","author":"Chastain","year":"2010","journal-title":"Astrobiology"},{"key":"ref_124","first-page":"137","article-title":"Methane production on rock and soil substrates by methanogens: Implications for life on Mars","volume":"420","author":"Kozup","year":"2009","journal-title":"Proceedings of the Bioastronomy 2007: Molecules, Microbes and Extraterrestrial Life ASP Conference Series"},{"key":"ref_125","doi-asserted-by":"crossref","first-page":"518","DOI":"10.3390\/microorganisms3030518","article-title":"The effects of perchlorates on the permafrost methanogens: Implication for autotrophic life on Mars","volume":"3","author":"Shcherbakova","year":"2015","journal-title":"Microorganisms"},{"key":"ref_126","doi-asserted-by":"crossref","first-page":"12336","DOI":"10.1038\/s41598-021-91882-0","article-title":"Transcriptional response to prolonged perchlorate exposure in the methanogen Methanosarcina barkeri and implications for Martian habitability","volume":"11","author":"Harris","year":"2021","journal-title":"Sci. Rep."},{"key":"ref_127","doi-asserted-by":"crossref","first-page":"87","DOI":"10.1016\/j.pss.2015.11.014","article-title":"Sensitivity and adaptability of methanogens to perchlorates: Implications for life on Mars","volume":"120","author":"Kral","year":"2016","journal-title":"Planet. Space Sci."},{"key":"ref_128","doi-asserted-by":"crossref","first-page":"181","DOI":"10.1016\/j.pss.2014.07.008","article-title":"Potential use of highly insoluble carbonates as carbon sources by methanogens in the subsurface of Mars","volume":"101","author":"Kral","year":"2014","journal-title":"Planet. Space Sci."},{"key":"ref_129","doi-asserted-by":"crossref","unstructured":"Wormald, R.M., Hopwood, J., Humphreys, P.N., Mayes, W., Gomes, H.I., and Rout, S.P. (2022). Methanogenesis from mineral carbonates, a potential indicator for life on Mars. Geosciences, 12.","DOI":"10.3390\/geosciences12030138"},{"key":"ref_130","doi-asserted-by":"crossref","unstructured":"Sinha, N., and Kral, T.A. (2018). Effect of UVC radiation on hydrated and desiccated cultures of slightly halophilic and non-halophilic methanogenic archaea: Implications for life on Mars. Microorganisms, 6.","DOI":"10.3390\/microorganisms6020043"},{"key":"ref_131","doi-asserted-by":"crossref","first-page":"951","DOI":"10.1089\/ast.2015.1319","article-title":"Enhanced radiation resistance of Methanosarcina soligelidi SMA-21, a new methanogenic archaeon isolated from a Siberian permafrost-affected soil in direct comparison to Methanosarcina barkeri","volume":"15","author":"Morozova","year":"2015","journal-title":"Astrobiology"},{"key":"ref_132","doi-asserted-by":"crossref","first-page":"63","DOI":"10.1016\/j.pss.2018.03.012","article-title":"Survival of non-psychrophilic methanogens exposed to Martian diurnal and 48-h temperature cycles","volume":"157","author":"Mickol","year":"2018","journal-title":"Planet. Space Sci."},{"key":"ref_133","doi-asserted-by":"crossref","unstructured":"Mickol, R.L., Laird, S.K., and Kral, T.A. (2018). Non-psychrophilic methanogens capable of growth following long-term extreme temperature changes, with application to Mars. Microorganisms, 6.","DOI":"10.3390\/microorganisms6020034"},{"key":"ref_134","doi-asserted-by":"crossref","first-page":"6","DOI":"10.1038\/s41598-019-56267-4","article-title":"Methanogenic archaea can produce methane in deliquescence-driven Mars analog environments","volume":"10","author":"Maus","year":"2020","journal-title":"Sci. Rep."},{"key":"ref_135","doi-asserted-by":"crossref","first-page":"197","DOI":"10.1089\/ast.2018.1877","article-title":"Response of methanogenic archaea from Siberian permafrost and non-permafrost environments to simulated Mars-like desiccation and the presence of perchlorate","volume":"19","author":"Serrano","year":"2019","journal-title":"Astrobiology"},{"key":"ref_136","doi-asserted-by":"crossref","first-page":"264","DOI":"10.1016\/j.pss.2010.07.012","article-title":"Low pressure and desiccation effects on methanogens: Implications for life on Mars","volume":"59","author":"Kral","year":"2011","journal-title":"Planet. Space Sci."},{"key":"ref_137","doi-asserted-by":"crossref","first-page":"167","DOI":"10.1016\/j.pss.2013.09.010","article-title":"Methanogen survival following exposure to desiccation, low pressure and Martian regolith analogs","volume":"89","author":"Kral","year":"2013","journal-title":"Planet. Space Sci."},{"key":"ref_138","doi-asserted-by":"crossref","first-page":"189","DOI":"10.1007\/s11084-006-9024-7","article-title":"Survival of methanogenic archaea from Siberian permafrost under simulated Martian thermal conditions","volume":"37","author":"Morozova","year":"2007","journal-title":"Orig. Life Evol. Biosph."},{"key":"ref_139","doi-asserted-by":"crossref","first-page":"198","DOI":"10.1016\/j.pss.2013.08.019","article-title":"Laser spectroscopic real time measurements of methanogenic activity under simulated Martian subsurface analog conditions","volume":"98","author":"Schirmack","year":"2014","journal-title":"Planet. Space Sci."},{"key":"ref_140","doi-asserted-by":"crossref","first-page":"1162","DOI":"10.1016\/j.icarus.2010.11.011","article-title":"Extended survival of several organisms and amino acids under simulated Martian surface conditions","volume":"211","author":"Johnson","year":"2011","journal-title":"Icarus"},{"key":"ref_141","doi-asserted-by":"crossref","first-page":"3345","DOI":"10.1111\/1462-2920.15494","article-title":"Mars\u2019 surface is not universally biocidal","volume":"23","author":"Hallsworth","year":"2021","journal-title":"Environ. Microbiol."},{"key":"ref_142","doi-asserted-by":"crossref","first-page":"785","DOI":"10.1089\/ast.2020.2237","article-title":"Mars extant life: What\u2019s next? Conference report","volume":"20","author":"Carrier","year":"2020","journal-title":"Astrobiology"},{"key":"ref_143","doi-asserted-by":"crossref","first-page":"116","DOI":"10.1038\/s41550-018-0676-9","article-title":"The next frontier for planetary and human exploration","volume":"3","author":"Beegle","year":"2019","journal-title":"Nat. Astron."},{"key":"ref_144","doi-asserted-by":"crossref","first-page":"741","DOI":"10.1089\/ast.2020.2386","article-title":"Earth-like habitable environments in the subsurface of Mars","volume":"21","author":"Tarnas","year":"2021","journal-title":"Astrobiology"},{"key":"ref_145","doi-asserted-by":"crossref","first-page":"345","DOI":"10.1016\/j.icarus.2012.03.019","article-title":"Habitable periglacial landscapes in Martian mid-latitudes","volume":"219","author":"Ulrich","year":"2012","journal-title":"Icarus"},{"key":"ref_146","doi-asserted-by":"crossref","first-page":"1395","DOI":"10.1073\/pnas.030538097","article-title":"Atmospheric energy for subsurface life on Mars?","volume":"97","author":"Weiss","year":"2000","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_147","doi-asserted-by":"crossref","first-page":"133","DOI":"10.1038\/ngeo1706","article-title":"Groundwater activity on Mars and implications for a deep biosphere","volume":"6","author":"Michalski","year":"2013","journal-title":"Nat. Geosci."},{"key":"ref_148","doi-asserted-by":"crossref","first-page":"21","DOI":"10.1038\/s41561-017-0015-2","article-title":"The Martian subsurface as a potential window into the origin of life","volume":"11","author":"Michalski","year":"2018","journal-title":"Nat. Geosci."},{"key":"ref_149","doi-asserted-by":"crossref","first-page":"470","DOI":"10.1016\/j.icarus.2008.05.004","article-title":"Mojave Mars simulant\u2014Characterization of a new geologic Mars analog","volume":"197","author":"Peters","year":"2008","journal-title":"Icarus"},{"key":"ref_150","doi-asserted-by":"crossref","first-page":"1735","DOI":"10.1128\/aem.55.7.1735-1741.1989","article-title":"Diffusion of the interspecies electron carriers H2 and formate in methanogenic ecosystems and its implications in the measurement of Km for H2 or formate uptake","volume":"55","author":"Boone","year":"1989","journal-title":"Appl. Environ. Microbiol."},{"key":"ref_151","doi-asserted-by":"crossref","first-page":"2064","DOI":"10.1128\/aem.54.8.2064-2068.1988","article-title":"Control of the life cycle of Methanosarcina mazei S-6 by manipulation of growth conditions","volume":"54","author":"Xun","year":"1988","journal-title":"Appl. Environ. Microbiol."},{"key":"ref_152","first-page":"410","article-title":"Isolation and characterization of a dimethyl sulfide-degrading methanogen, Methanolobus siciliae HI350, from an oil well, characterization of M. siciliae T4\/MT, and emendation of M. siciliae","volume":"41","author":"Ni","year":"1991","journal-title":"Int. J. Syst. Evol. Microbiol."},{"key":"ref_153","unstructured":"Sowers, K., and Noll, K. (1995). Techniques for Anaerobic Growth, Cold Spring Harbor Laboratory Press."},{"key":"ref_154","doi-asserted-by":"crossref","first-page":"10","DOI":"10.1128\/MMBR.00020-19","article-title":"Energy conservation and hydrogenase function in methanogenic archaea, in particular the genus Methanosarcina","volume":"83","author":"Mand","year":"2019","journal-title":"Microbiol. Mol. Biol. Rev."},{"key":"ref_155","doi-asserted-by":"crossref","first-page":"513","DOI":"10.1007\/s00248-006-9049-5","article-title":"Microbial maintenance: A critical review on its quantification","volume":"53","year":"2007","journal-title":"Microb. Ecol."},{"key":"ref_156","doi-asserted-by":"crossref","first-page":"1555","DOI":"10.1038\/s41564-025-02048-x","article-title":"Defining ultra-slow-growing extremophilic microorganisms as aeonophiles","volume":"10","author":"Lloyd","year":"2025","journal-title":"Nat. Microbiol."},{"key":"ref_157","doi-asserted-by":"crossref","first-page":"537","DOI":"10.1346\/CCMN.2000.0480506","article-title":"Geology and characterization of two hydrothermal nontronites from weathered metamorphic rocks at the Uley graphite mine, South Australia","volume":"48","author":"Keeling","year":"2000","journal-title":"Clays Clay Miner."},{"key":"ref_158","doi-asserted-by":"crossref","first-page":"223","DOI":"10.1346\/000986002760832829","article-title":"Site occupancies by iron in nontronites","volume":"50","author":"Gates","year":"2002","journal-title":"Clays Clay Miner."},{"key":"ref_159","unstructured":"van Olphen, H., and Fripiar, J. (1979). Data Handbook for Clay Materials and Other Non-Metallic Minerals, Pergamon Press. [1st ed.]."},{"key":"ref_160","doi-asserted-by":"crossref","first-page":"819","DOI":"10.1089\/ast.2006.6.819","article-title":"Methane production by methanogens following an aerobic washing procedure: Simplifying methods for manipulation","volume":"6","author":"McAllister","year":"2006","journal-title":"Astrobiology"},{"key":"ref_161","doi-asserted-by":"crossref","first-page":"91","DOI":"10.1007\/BF00408015","article-title":"Characterization of Methanococcus maripaludis sp. nov., a new methanogen isolated from salt marsh sediment","volume":"135","author":"Jones","year":"1983","journal-title":"Arch. Microbiol."},{"key":"ref_162","doi-asserted-by":"crossref","first-page":"107","DOI":"10.1186\/s12934-016-0500-0","article-title":"Metabolic processes of Methanococcus maripaludis and potential applications","volume":"15","author":"Goyal","year":"2016","journal-title":"Microb. Cell Fact."},{"key":"ref_163","doi-asserted-by":"crossref","first-page":"57","DOI":"10.1007\/BF00428580","article-title":"Lack of peptidoglycan in the cell walls of Methanosarcina barkeri","volume":"113","author":"Kandler","year":"1977","journal-title":"Arch. Microbiol."},{"key":"ref_164","doi-asserted-by":"crossref","first-page":"1481","DOI":"10.1099\/00221287-131-6-1481","article-title":"Spontaneous protoplast formation by Methanosarcina barkeri","volume":"131","author":"Davis","year":"1985","journal-title":"Microbiology"},{"key":"ref_165","first-page":"267","article-title":"Characterization of Methanosarcina barkeri MST and 227, Methanosarcina mazei S-6T, and Methanosarcina vacuolata Z-761T","volume":"41","author":"Boone","year":"1991","journal-title":"Int. J. Syst. Evol. Microbiol."},{"key":"ref_166","doi-asserted-by":"crossref","first-page":"303","DOI":"10.1016\/j.colsurfb.2014.12.035","article-title":"Mechanical and cell-to-cell adhesive properties of aggregated Methanosarcina","volume":"126","author":"Milkevych","year":"2015","journal-title":"Colloids Surf. B Biointerfaces"},{"key":"ref_167","doi-asserted-by":"crossref","first-page":"141","DOI":"10.1007\/BF00415722","article-title":"Chemical composition of the peptidoglycan-free cell walls of methanogenic bacteria","volume":"118","author":"Kandler","year":"1978","journal-title":"Arch. Microbiol."},{"key":"ref_168","doi-asserted-by":"crossref","first-page":"43","DOI":"10.1099\/00207713-50-1-43","article-title":"Phylogenetic analysis of 18 thermophilic Methanobacterium isolates supports the proposals to create a new genus, Methanothermobacter gen. nov., and to reclassify several isolates in three species, Methanothermobacter thermautotrophicus comb. nov., Methanothermobacter wolfeii comb. nov., and Methanothermobacter marburgensis sp. nov","volume":"50","author":"Wasserfallen","year":"2000","journal-title":"Int. J. Syst. Evol. Microbiol."},{"key":"ref_169","doi-asserted-by":"crossref","first-page":"27","DOI":"10.1128\/jb.163.1.27-36.1985","article-title":"Enzymatic lysis of the pseudomurein-containing methanogen Methanobacterium formicicum","volume":"163","author":"Bush","year":"1985","journal-title":"J. Bacteriol."},{"key":"ref_170","doi-asserted-by":"crossref","unstructured":"Hassa, J., Wibberg, D., Maus, I., P\u00fchler, A., and Schl\u00fcter, A. (2019). Genome analyses and genome-centered metatranscriptomics of Methanothermobacter wolfeii strain SIV6, isolated from a thermophilic production-scale biogas fermenter. Microorganisms, 8.","DOI":"10.3390\/microorganisms8010013"},{"key":"ref_171","doi-asserted-by":"crossref","first-page":"29","DOI":"10.1016\/j.clay.2019.03.019","article-title":"Methane production and carbon assimilation in nontronite at 25 \u00b0C","volume":"174","author":"Ruiz","year":"2019","journal-title":"Appl. Clay Sci."},{"key":"ref_172","doi-asserted-by":"crossref","first-page":"20192410","DOI":"10.1098\/rspb.2019.2410","article-title":"Earth\u2019s earliest and deepest purported fossils may be iron-mineralized chemical gardens","volume":"286","author":"McMahon","year":"2019","journal-title":"Proc. R. Soc. B Biol. Sci."},{"key":"ref_173","doi-asserted-by":"crossref","first-page":"603","DOI":"10.1016\/j.mimet.2006.05.007","article-title":"Washing methanogenic cells with the liquid fraction from a Mars soil simulant and water mixture","volume":"67","author":"Ormond","year":"2006","journal-title":"J. Microbiol. Methods"}],"container-title":["Microorganisms"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-2607\/14\/7\/1496\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,7,8]],"date-time":"2026-07-08T14:40:11Z","timestamp":1783521611000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-2607\/14\/7\/1496"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,7,8]]},"references-count":173,"journal-issue":{"issue":"7","published-online":{"date-parts":[[2026,7]]}},"alternative-id":["microorganisms14071496"],"URL":"https:\/\/doi.org\/10.3390\/microorganisms14071496","relation":{},"ISSN":["2076-2607"],"issn-type":[{"value":"2076-2607","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,7,8]]}}}