Antarctic fungi survive Martian conditions on ISS

Tiny fungi from Antarctica have survived hostile conditions similar to those on Mars simulated on the International Space Station (ISS), scientists including one of Indian-origin have found.
The results provide new information for the search for life on the red planet, researchers said.
After 18 months on board in conditions similar to those on Mars, more than 60 per cent of the fungal cells remained intact, with stable DNA.
Lichens from the Sierra de Gredos (Spain) and the Alps (Austria) were also sent into space for the same experiment.
The McMurdo Dry Valleys, located in the Antarctic, are considered to be the most similar earthly equivalent to Mars.

Only cryptoendolithic microorganisms, capable of surviving in cracks in rocks, and certain lichens can withstand such harsh climatological conditions.

Researchers, including Kasthuri Venkateswaran from NASA's Jet Propulsion Laboratory in US, collected samples of two species of cryptoendolithic fungi - Cryomyces antarcticus and Cryomyces minteri.
The fungi were placed in cells (1.4cm in diameter) on a platform for experiments known as EXPOSE-E, developed by the European Space Agency to withstand extreme environments.
The platform was sent to the ISS. For 18 months half of the Antarctic fungi were exposed to Mars-like conditions.
Samples were subjected to ultra-violet radiation as if on Mars (higher than 200 nanometres) and others to lower radiation, including separate control samples.

"The most relevant outcome was that more than 60 per cent of the cells of the endolithic communities studied remained intact after 'exposure to Mars', or rather, the stability of their cellular DNA was still high," said Rosa de la Torre Noetzel from Spain's National Institute of Aerospace Technology (INTA), co-researcher on the project.
"The results help to assess the survival ability and long-term stability of microorganisms and bioindicators on the surface of Mars, information which becomes fundamental and relevant for future experiments centred around the search for life on the red planet," said De la Torre.
Researchers also studied two species of lichens which can withstand extreme high-mountain environments, with half of the specimens also being exposed to Martian conditions.

Another range of samples was subjected to an extreme space environment. The effect of ultra-violet extraterrestrial radiation on half of the samples was also examined.
After the year-and-a-half-long voyage, the two species of lichens 'exposed to Mars' showed double the metabolic activity of those that had been subjected to space conditions.
The results showed subdued photosynthetic activity or viability in the lichens exposed to the harsh conditions of space (2.5 per cent of samples), similar to that presented by the fungal cells (4.11 per cent).
In this space environment, 35 per cent of fungal cells were also seen to have kept their membranes intact, a further sign of the resistance of Antarctic fungi.

The study was published in the journal Astrobiology.