The Amazing Journey of Cryomyces antarcticus from Antarctica to Space

Abstract

The cryptoendolithic endemic black fungus Cryomyces antarcticus was first isolated from sandstone collected at Linnaeus Terrace, McMurdo Dry Valleys, Southern Victoria Land, Antarctica, by E.I. Friedmann in 1982, but published as a new species and genus in 2005. The McMurdo Dry Valleys are the coldest hyperarid desert on Earth and one of the best terrestrial analogues for Mars. There, microbes last chance for survival is to find refuge inside the porous rocks. The ability of C. antarcticus to withstand stresses has been widely demonstrated, and its stunning resistance is nowadays regarded as one of the best eukaryotic test organisms for astrobiological researches. Its extreme tolerance has been widely reported in about 10 years of space and ground experiments. It maintained survival, DNA integrity, ultrastructure stability and rapid metabolic activity recovery after 18 months expo- sure to space and Mars-like conditions in low Earth orbit (LEO) in the frame of ESA’s LIFE (LIchens and Fungi Experiment) and ESA-ASI’s BIOMEX (BIOlogy and Mars EXperiment) projects. Further investigations of space simulations on Earth within the STARLIFE project, aimed at characterizing the effect of different kinds of ionizing radiation (gamma radiation and α-particle), have shown its bewildering ability to resist stress radiation beyond all expectations. The resistance of fungal biomol- ecules will be further investigated within the recently approved ESA-ASI BIOSIGN (BIOSIGnature and habitable Niches) project.