{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,10]],"date-time":"2026-10-10T05:56:59Z","timestamp":1791611819696,"version":"4.3.4"},"reference-count":106,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2019,11,14]],"date-time":"2019-11-14T00:00:00Z","timestamp":1573689600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004955","name":"\u00d6sterreichische Forschungsf\u00f6rderungsgesellschaft","doi-asserted-by":"publisher","award":["853615, 859293"],"award-info":[{"award-number":["853615, 859293"]}],"id":[{"id":"10.13039\/501100004955","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Life"],"abstract":"<jats:p>Lipids and amino acids are regarded as important biomarkers for the search for extraterrestrial life in the Solar System. Such biomarkers may be used to trace methanogenic life on other planets or moons in the Solar System, such as Saturn\u2019s icy moon Enceladus. However, little is known about the environmental conditions shaping the synthesis of lipids and amino acids. Here, we present the lipid production and amino acid excretion patterns of the methanogenic archaeon Methanothermococcus okinawensis after exposing it to different multivariate concentrations of the inhibitors ammonium, formaldehyde, and methanol present in the Enceladian plume. M. okinawensis shows different patterns of lipid and amino acids excretion, depending on the amount of these inhibitors in the growth medium. While methanol did not show a significant impact on growth, lipid or amino acid production rates, ammonium and formaldehyde strongly affected these parameters. These findings are important for understanding the eco-physiology of methanogens on Earth and have implications for the use of biomarkers as possible signs of extraterrestrial life for future space missions in the Solar System.<\/jats:p>","DOI":"10.3390\/life9040085","type":"journal-article","created":{"date-parts":[[2019,11,14]],"date-time":"2019-11-14T10:56:34Z","timestamp":1573728994000},"page":"85","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":20,"title":["Membrane Lipid Composition and Amino Acid Excretion Patterns of Methanothermococcus okinawensis Grown in the Presence of Inhibitors Detected in the Enceladian Plume"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5705-5075","authenticated-orcid":false,"given":"Ruth-Sophie","family":"Taubner","sequence":"first","affiliation":[{"name":"Archaea Physiology &amp; Biotechnology Group, Archaea Biology and Ecogenomics Division, Department of Ecogenomics and Systems Biology, Universit\u00e4t Wien, 1010 Vienna, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lydia M. F.","family":"Baumann","sequence":"additional","affiliation":[{"name":"Institute for Geology, Center for Earth System Research and Sustainability, Universit\u00e4t Hamburg, 20146 Hamburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4858-9443","authenticated-orcid":false,"given":"Thorsten","family":"Bauersachs","sequence":"additional","affiliation":[{"name":"Institute of Geosciences, Department of Organic Geochemistry, Christian-Albrechts-Universit\u00e4t, 24118 Kiel, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8662-8848","authenticated-orcid":false,"given":"Elisabeth L.","family":"Clifford","sequence":"additional","affiliation":[{"name":"Department of Limnology and Bio-Oceanography, Universit\u00e4t Wien, 1010 Vienna, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Barbara","family":"M\u00e4hnert","sequence":"additional","affiliation":[{"name":"Department of Limnology and Bio-Oceanography, Universit\u00e4t Wien, 1010 Vienna, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Barbara","family":"Reischl","sequence":"additional","affiliation":[{"name":"Archaea Physiology &amp; Biotechnology Group, Archaea Biology and Ecogenomics Division, Department of Ecogenomics and Systems Biology, Universit\u00e4t Wien, 1010 Vienna, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Richard","family":"Seifert","sequence":"additional","affiliation":[{"name":"Institute for Geology, Center for Earth System Research and Sustainability, Universit\u00e4t Hamburg, 20146 Hamburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8572-0060","authenticated-orcid":false,"given":"J\u00f6rn","family":"Peckmann","sequence":"additional","affiliation":[{"name":"Institute for Geology, Center for Earth System Research and Sustainability, Universit\u00e4t Hamburg, 20146 Hamburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9746-3284","authenticated-orcid":false,"given":"Simon K.-M. R.","family":"Rittmann","sequence":"additional","affiliation":[{"name":"Archaea Physiology &amp; Biotechnology Group, Archaea Biology and Ecogenomics Division, Department of Ecogenomics and Systems Biology, Universit\u00e4t Wien, 1010 Vienna, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniel","family":"Birgel","sequence":"additional","affiliation":[{"name":"Institute for Geology, Center for Earth System Research and Sustainability, Universit\u00e4t Hamburg, 20146 Hamburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,11,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"507","DOI":"10.1038\/nrmicro2815","article-title":"The early evolution of lipid membranes and the three domains of life","volume":"10","author":"Lombard","year":"2012","journal-title":"Nat. Rev. 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