Cyanobacteria from Extreme Deserts to Space

Abstract

The development of space technology makes the exposure of organisms and molecules to the space environment possible by using the ESA Biopan and Expose facilities and NASA nanosatellites; the aim is to decipher the origin, evolution and distribution of life on Earth and in the Universe. The study of microbial communities thriving in lithic habitats in cold and hot deserts is gathering appreciation when dealing with the limits of life as we know it, the identification of biosignatures for searching life beyond Earth and the validation of the (litho)-Panspermia theory. Cyanobacteria of the genus Chroococcidiopsis dominate rock-dwelling communities in extreme deserts that are considered terrestrial analogues of Mars, like the Dry Valleys in Antarctica, the Atacama Desert in Chile or the Mojave Desert in California. The extraordinary tolerance of these cyanobacteria towards desiccation, ionizing and UV radiation makes them suitable experimental strains which have been already used in astrobiological experiments and already selected for future space missions. Evidence gained so far supports the use of desert cyanobacteria to develop life support systems and in-situ resource utilization for the human space exploration and settlement on the Moon or Mars.

RNA-based molecular survey of biodiversity of limestone tombstone microbiota in response to atmospheric sulphur pollution

“…(99% similarity) has been detected in the biofilm samples collected in the urban area of Cambridge. This micro-organism occurs in hypolithic and endolithic communities worldwide, as in the Dry Valleys in Antarctica or the Atacama Desert, where it persists in a dry ametabolic state for prolonged periods (Billi et al 2013). The genetic potential of microbial sulphur metabolism was analysed by amplifying key genes of known sulphuroxidation and sulphate-reducing pathways.…”

Sustainable life support on Mars – the potential roles of cyanobacteria

“…Water requirements could be further reduced by growing terrestrial cyanobacteria as biofilms, directly on the surface of Martian rocks, in a semi-closed environment where suitable temperature, pressure and moisture are provided. Such a growth system could be relatively close to the natural lifestyle of rock-dwelling cyanobacteria, noteworthy in terrestrial deserts (see, e.g., Friedmann & Ocampo 1976;de la Torre et al 2003;Warren-Rhodes et al 2006 andBilli et al 2013) but with more favourable moisture, UV protection and temperatures.…”

“…They thrive in the most extreme habitable conditions on Earth, such as in dry deserts and ice lakes of Antarctica, and within ices of high Arctic seas (Wierzchos et al 2006;Scalzi et al 2012). Some have an outstanding resistance to environmental factors occurring on Mars's surfaces, including ultraviolet (UV) and ionizing radiation (see, for instance, Billi et al 2013 andThomas et al 2006) and can survive in space when protected from UV radiation .…”

Nitrogen fixing cyanobacteria: their diversity, ecology and utilisation with special reference to rice cultivation

“…It could also be a reflection of their long ancestry originating from the primitive Earth, which was inhospitable to most life forms. These features that certain cyanobacteria show in common with other extremophilic microorganisms such as exposure to high light, tolerance to UV radiation, desiccation, the ability to withstand very high to freezing temperatures and tolerance to acidity and alkalinity make them ideal candidates for Astrobiological studies (Seckbach, 2006;Francis et al, 2010;Billi et al, 2013) and in the search for novel…”