Biological methane production under putative Enceladus-like conditions

Author(s)
Ruth-Sophie Taubner, Patricia Pappenreiter, Jennifer Zwicker, Daniel Smrzka, Christian Pruckner, Philipp Kolar, Sébastien Bernacchi, Arne H Seifert, Alexander Krajete, Wolfgang Bach, Jörn Peckmann, Christian Paulik, Maria G Firneis, Christa Schleper, Simon K-M R Rittmann
Abstract

The detection of silica-rich dust particles, as an indication for ongoing hydrothermal activity, and the presence of water and organic molecules in the plume of Enceladus, have made Saturn’s icy moon a hot spot in the search for potential extraterrestrial life. Methanogenic archaea are among the organisms that could potentially thrive under the predicted conditions on Enceladus, considering that both molecular hydrogen (H2) and methane (CH4) have been
detected in the plume. Here we show that a methanogenic archaeon, Methanothermococcus okinawensis, can produce CH4 under physicochemical conditions extrapolated for Enceladus. Up to 72% carbon dioxide to CH4 conversion is reached at 50 bar in the presence of potential inhibitors. Furthermore, kinetic and thermodynamic computations of low-temperature serpentinization indicate that there may be sufficient H2 gas production to serve as a substrate for CH4 production on Enceladus. We conclude that some of the CH4 detected in the plume of Enceladus might, in principle, be produced by methanogens.

Organisation(s)
Department of Astrophysics, Department of Geology
External organisation(s)
Johannes Kepler Universität Linz, Krajete GmbH, Austria, Universität Bremen, Universität Hamburg, University of Vienna
Journal
Nature Communications
Volume
9
No. of pages
11
ISSN
2041-1723
DOI
https://doi.org/10.1038/s41467-018-02876-y
Publication date
02-2018
Peer reviewed
Yes
Austrian Fields of Science 2012
103003 Astronomy, 105105 Geochemistry, 106022 Microbiology
Keywords
ASJC Scopus subject areas
General Physics and Astronomy, General Chemistry, General Biochemistry,Genetics and Molecular Biology
Portal url
https://ucrisportal.univie.ac.at/en/publications/cde6fab1-979b-4b99-9724-9a5490effeee