Chemolithotrophy on the Noachian Martian brecciaNWA 7034 via experimental microbialbiotransformation

Multiple lines of evidence indicate an active hydrogeological history of Mars andchemolithoautotrophy-suited environments within its Noachian terrains. As a result, one ofthe primary aims of upcoming missions to Mars is to search for signs of ancient life. Here wereport on laboratory-scaled microbially assisted chemolithoautotrophic biotransformation ofthe Noachian Martian breccia Northwest Africa (NWA) 7034 composed of ancient (~4.5 Gyrold) crustal materials from Mars. Nanoanalytical hyperspectral analysis provides clues for thetrafficking and distribution of meteorite inorganic constituents in the microbial cell. Wedecipher biomineralization patterns associated with the biotransformation and revealmicrobial nanometer-sized lithologies located inside the cell and on its outer surface layer.These investigations provide an opportunity to trace the putative bioalteration processes ofthe Martian crust and to assess the potential biogenicity of Martian materials.