| Project Detail |
Earth’s microbes get a taste of Martian material in a reverse exploration for life
While we usually think of food chains as larger organisms eating smaller ones, not all food chains are made solely of organic links. Chemolithotrophs are a very diverse group of microbes that live here on Earth and can obtain all the nutrients, and thus energy, they require for living from the oxidation of inorganic compounds. The EU-funded BIOMAMA project is letting these microbes loose on Martian materials in the first-of-its-kind effort to identify biosignatures associated with successful feeders. In laboratory, field and space exposure experiments, the team will probe processes with nanoscale and atomic resolution to help interpret signs of life in samples returned from future Mars missions.
The search for biologically driven alterations on Mars and its potential as habitat for past or present life is a primary aim of the upcoming Mars exploration missions. While a range of environments that would have been well suited to support a potential chemolithotrophy on Mars have been proposed, our understanding of putative biosignatures to be targeted in Martian materials is still poor. A valuable source of information can be extracted from microbial fingerprints of chemolithotrophic life based on Martian materials (Martian meteorites, regolith simulants). Chemolithotrophic microorganisms employ an astonishing number of metabolic pathways to extract energy from diverse inorganic electron donors/acceptors, shaping global biogeochemical cycles. Using a holistic approach based on laboratory, field and space exposure experiments, we propose to investigate interactions of Earth’s various chemolithoautotrophs with Martian materials. The bottom-up exploration of mineral-microbial interactions for different chemolithotrophs cultivated on Martian materials as the sole energy sources, will decipher mineral and metabolic biosignatures associated with these cases. This project explores unique microbial interactions with extraterrestrial materials down to the nanoscale and atomic resolution utilizing a comprehensive toolbox of cutting-edge techniques. BioMaMa will identify preservable biomarkers/biosignatures of chemolithotrophic life on Martian materials after the exposure to simulated Martian conditions at low Earth orbit and ground-based facilities. A complex approach will be used to investigate meteorite-microbial interactions in Mars-analogue sites on Earth. The extensive knowledge gained from BioMaMa will help to understand and critically interpret the results of future Mars exploration missions (ExoMars 2020). These studies will lay the foundation for efficient nanoanalytical spectroscopy of returned Mars samples, to critically assess their potential biogenicity. |
