Organisms thriving on Earth under extreme conditions suggest that live could exist under similar conditions in other planets. Cyanobacteria such as Chroococcidiopsis, from extremely hot and cold deserts, provide unique models to gain an insight on the limits of life on Earth and search extinct or extant life on other planets. In the McMurdo Dry Valleys, Antarctica, Chroococcidiopsis finds refuge in porous rocks and thus escapes the outside hostile climate, that makes this environment the closest terrestrial analogue of Mars. The capability of desert Chroococcidiopsis to survive extreme desiccation (anhydrobiosis) and high doses of both ionizing (up to 15 KGy ) and ultraviolet (simulated Martian UV flux) radiation, makes it an appropriate model-test in astrobiology.

Cryptoendolithic growth of Chroococcidiopsis in a lichen-dominated microbial community, Ross Desert (McMurdo Dry Valleys, Antarctica), kindly provided by E. Imre Friedmann

Involved scientists: Daniela Billi

Collaborations: I.Friedmann (NASA Ames Research Center, Space Science Division, CA, USA), C. Cockell (Planetary and Space Science Research Institute, Open University, Milton, UK), S. Onori (Università della Tuscia, Viterbo).

Publications