Meet Planococcus halocryophilus, who thrives in a salty brine –15ºC (5F), the coldest temperature ever reported for bacterial growth. This bacterium lives around the McGill High Arctic Research Station, on Ellesmere Island in the Canadian high Arctic, where temps are similar to Mars. 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.

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