21-EPN-FT1-016: Metabolic responses of Antarctic melanised microorganism to simulated Martian conditions
Visit by Ilaria Catanzaro, University of Tuscia (Italy) to TA2.19 Center for Microbial Life Detection, Medical University Graz (Austria).
Dates of visit: 30 May – 03 June 2022
Report Summary: Current hostile conditions on the surface of Mars entail that, if any life form has ever existed on the planet, it may have adopted survival strategies like those evolved by terrestrial microorganisms inhabiting extreme environments e.g. Antarctica. There, one of the most common strategies observed is the cryptoendolithic microbial growth where free-living black fungi living along with algae and lichens within rocky interstices serve as a shield from excessive harmful solar radiation, and their extremotolerance can be mainly due to the presence of thick, highly melanised cell walls.
The ability of these cryptoendolytic microorganisms to thrive under extreme conditions raises the question of whether they cope with them by also regulating their metabolic expression in addition to melanin production, and whether a hypothetical microbial life on Mars could ever have arisen with similar adaptive strategies. In this optic, this study aimed to examin the metabolic regulation of melanised, cryptoendolithic microorganisms in martian scenario. To achieve this goal, colonies of the cryptoendolithic black fungus Cryomyces antarcticus previously exposed to simulated martian conditions such as perchlorates, sulfatic regolith soil and γ radiation, were then analysed with NMR spectrometry at the Center for Microbial Life Detection of the Medical University of Graz. Sample preparation and analysis were carried out in the Facility using standard protocols. Although only preliminary data are available at the time of report writing, significant differences in fungal metabolic expression were observed between the different simulated martian conditions tested.