Ispravci

Bacterium from Canadian High Arctic Offers Clues to Possible Life On Mars.

May 23, 2013 — The temperature in the permafrost on Ellesmere Island in the Canadian high Arctic is nearly as cold as that of the surface of Mars.

So the recent discovery by a McGill University led team of scientists of a bacterium that is able to thrive at -15ºC, the coldest temperature ever reported for bacterial growth, is exciting.

The bacterium offers clues about some of the necessary preconditions for microbial life on both the Saturn moon Enceladus and Mars, where similar briny subzero conditions are thought to exist.

The team of researchers, led by Prof. Lyle Whyte and postdoctoral fellow Nadia Mykytczuk, both from the Dept. of Natural Resource Sciences at McGill University, discovered Planococcus halocryophilus OR1 after screening about 200 separate High Arctic microbes looking for the microorganism best adapted to the harsh conditions of the Arctic permafrost.

"We believe that this bacterium lives in very thin veins of very salty water found within the frozen permafrost on Ellesmere Island," explains Whyte.

"The salt in the permafrost brine veins keeps the water from freezing at the ambient permafrost temperature (~-16ºC), creating a habitable but very harsh environment.

It's not the easiest place to survive but this organism is capable of remaining active (i.e. breathing) to at least -25ºC in permafrost."