Bacteria discovered in high Arctic permafrost may help scientists better understand how similar microbes could exist on Mars. Known as the OR1 strain of Planococcus halocryophilus, the microbes have been observed multiplying and thriving at a temperature of just five degrees Fahrenheit. This strain of microbe still remains active even at temperatures as low as -13 degrees.
The Canadian-led research team that made the discovery was headed by Lyle White, a microbiologist from McGill University, along with Nadia Mykytczuk, a post-doctoral research scientist.
"You look at permafrost, you think of this frozen dead world, but it's not," said Whyte. "The study that we show here indicates there are organisms that are... capable of surviving and reproducing in the conditions in which it came from - the permafrost."
The bacteria were collected as part of a 2004 NASA-sponsored drilling excursion aimed at testing methods to take core samples from the frozen wastes of Mars. Over 200 strains of bacteria were collected from the sample taken from Ellesmere Island, Nunavut. Whyte and his team were commissioned by NASA with the task of ensuring that the core samples were not contaminated by foreign microbes. The space agency handed the samples over to Whyte when they had finished with his research, sparking years of research by Whyte's team.
At just five degrees above zero, the population of Planococcus halocryophilus was seen doubling every 40 days. Whyte and his team grew the samples in an 18 percent salt water solution to keep the frigid water in which the bacteria lived from freezing. This is about five times saltier than normal sea water. In the wild, these bacteria survive in tiny cracks in the ice filled with a heavy salt solution formed when the ice around the fissure freezes, expelling their salt content into the narrow cavity.
Of more than 200 varieties of microbes grown by Whyte's team, it was Planococcus that was best-adapted to Mars-like conditions. Researchers discovered that the bacteria had protective membranes and proteins well-designed for the harsh environment. Chemicals found within the cells act as a type of antifreeze that also helps to protect against high salt concentrations.
Ellesmere Island lies within the Canadian Arctic Archipelago at over 79 degrees north. With over 75,000 square miles of land, it is the world's 10th largest island, but has a population of under 200 residents.
"What we can learn from this microbe may tell us a lot about how similar microbial life may exist elsewhere in the solar system," Whyte said.
