Discovery of Permafrost Microbes Offers Proof of Possible Life On Mars

Our fascination with Mars and the quest to locate possible life on it is never-ending. And adding fuel to the curiosity are the new research findings from a study conducted by the University of McGill, Canada. A team of scientists from the University has discovered a bacterium that is able to flourish at -15⁰C, temperature that is reported as the coldest ever for any kind of bacterial growth.

The sign of life discovered in the permafrost on Ellesmere Island in the Canadian high Arctic by a team of researchers led by Prof. Lyle Whyte and postdoctoral fellow, Nadia Mykytczuk, of the Department of Natural Resource Sciences at the university suggests clues regarding certain essential prerequisite for microbial life on Mars as well as Saturn's moon Enceladus.

This assumption is brought about by the fact that the temperature in the permafrost on Ellesmere Island is similar to that of Mars and Enceladus, where such salty subzero environment is thought to exist.

According to a news release issued by the McGill University on 22 May, the microbe Planococcus halocryophilus OR1 was discovered by the researchers after screening about 200 separate High Arctic microbes looking for the microorganism best adapted to the harsh environment of the Arctic permafrost.

According to the statement published in the news release by one of the leading researchers of the study Prof Lyle Whyte, the bacterium is believed to thrive in the very thin deposits of salty water found within the frozen permafrost of Ellesmore Island.

"The salt in the permafrost brine veins keeps the water from freezing at the ambient permafrost temperature (~-16⁰C), 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 -25⁰C in the permafrost.", says Whyte.

The team found that certain significant alterations in the cell structure and its function and increased quantity of cold-adapted proteins enables the bacterium to adapt to the extremely cold and briny conditions in the permafrost. The modifications comprise of certain changes to the membrane that envelope the bacterium and shield it from the hostile condition of its habitat.

The high levels of compound within the bacterial cell, the microbe appeared to maintain, perform the role of molecular antifreeze provided protection for it from the extremely briny conditions outside along with preventing the bacterium from freezing solid.

Even as the researchers are optimistic about the potential of the microbe to shed light on possible life that may exist elsewhere in the solar system, they fear that the carbon dioxide emissions from the microbe may play a harmful role in the subzero environments such as that of the High Arctic leading to melting permafrost, one of the outcome of global warming.

The research was funded by the Natural Sciences and Engineering Research Council of Canada CREATE Canadian Astrobiology Training Program, Canadian Space Agency, the Polar Continental Shelf Programme, Canada Research Chairs Programme and the Canada Foundation for Innovation.