Mars exploration begins on Earth: Systematic comparison of the anaerobic, intact and cultivable microbiome of extreme, anoxic, Mars-analogue environments.

Abstract

The concept of present and/or past extraterrestrial life is thrilling and tackled intensively throughout the last decades, yet remains notional. Some regions of extraterrestrial bodies (e.g. the Mars) are in general considered as habitable; however, are ruled by extreme physical and chemical variables, which constrain the possibility of life. Similar settings (at least to a certain extent) exist on Earth and function as analogue model sites in many studies to elucidate basic information on the limits of life. One crucial feature, which distinguishes Earth from extraterrestrial bodies, is the absence of oxygen in the atmosphere. Terrestrial Mars analogue, anoxic settings are hardly described, in par-ticular with respect on the hosted microbial communities. The MASE (Mars Analogues for Space Exploration) project tackled to understand specifically anaerobic life thriving in a number of various Mars analogue settings. Within the frame of this project, a diverse set of extreme and anoxic Mars analogue environments were sampled and microbiologically investigated by combining cultivation based and cultivation-independent analyses. This study included (i) a widescale cultivation approach targeting the anaerobic microbial fraction and (ii) an amplicon sequencing approach focusing on the viable Archaeome and Bacteriome.