Methanogenesis from Mineral Carbonates, a Potential Indicator for Life on Mars

Priorities for the exploration of Mars involve identification and observation biosignatures that indicate existence life on planet. The atmosphere composition sediments suggest suitability anaerobic chemolithotrophic metabolism. Carbonates are often considered as morphological biosignatures, such stromatolites, but have not been potential electron acceptors. Within present study, hydrogenotrophic methanogen enrichments were generated from had received significant quantities lime industrial processes (lime kiln/steel production). These then supplemented with calcium carbonate powder or marble chips a sole source carbon. microcosms saw release inorganic carbon into liquid phase, which was subsequently removed, resulting in generation methane, 0.37 ± 0.09 mmoles methane observed steel sediment powder. dominated by Methanobacterium sp., whilst lime/marble more diverse, containing varying proportions Methanomassiliicoccus, Methanoculleus Methanosarcina sp. In all microcosm experiments, acetic acid detected phase. Our results methanogenesis should be when determining Mars.