A microbe discovered in the Canadian high Arctic thrives at the coldest temperature known for bacterial growth.
Researchers found the newly discovered bacterium, Planococcus halocryophilus OR1, in permafrost — permanently frozen ground — on Ellesmere Island. The organism thrives at 5 degrees Fahrenheit (minus 15 degrees Celsius), and holds clues to adaptations that might be necessary for life on Mars or Saturn's moon Enceladus, where temperatures are well below freezing.
The microbe lives inside veins of salty water, and can survive because the salt prevents the water in the veins from freezing, study leader Lyle Whyte of McGill University in Montreal said in a statement. The bacterium can remain active and breathing at temperatures down to at least minus 13 degrees F (minus 25 degrees C) in permafrost, Whyte said.
Whyte and his team studied the bacterium's genome sequence and found that P. halocryophilus OR1 withstands the cold and salt thanks to modifications in its cell structure, cell function and an abundance of cold-adapted proteins. Changes in the cell membrane that protects the bacterium are one example of such modifications.
The bacterium also appears to contain high levels of a compound that works as molecular antifreeze, as well as protecting the cell from the salty fluid in its environment.
These microbes might be bad news for global warming, which is melting permafrost in Arctic regions. Permafrost contains dead organic matter that bacteria can break down, releasing carbon dioxide and venting the greenhouse gas to the atmosphere. More of these microbes mean more greenhouse gas gets released.
Still, Whyte calls the bacterium "our cold temperature champion," adding "what we can learn from this microbe may tell us a lot about how similar microbial life may exist elsewhere in the solar system."
It's not the first time life has been found in permafrost conditions. Cold-loving extremophiles, called psychrophiles, are most often bacteria, fungi or algae. These hardy microbes have been found living beneath sheets of ice in Siberia and Antarctica, where temperatures range from 23 to 68 degrees F (minus 5 to 20 degrees C).
A 2006 review article in the journal EMBO Reports describes some of the adaptations organisms have developed for surviving the challenges of life at these frigid temperatures. These challenges include slowed rates of biochemical reactions and more viscous fluid environments.
Copyright 2013 LiveScience, a TechMediaNetwork company. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.
Damaging thunderstorms will target an area that has been hit by heavy rain and rising floodwaters in recent days into Saturday night.
Following a storm that brought snow Thursday night, another snowstorm will threaten travelers across the Upper Midwest through Saturday night.
Both short-term and long-term flooding will continue over a large part of the central United States as more rain falls and runoff continues through next week.
While strong winds and cold dominated weather headlines at PyeongChang, South Korea, during this Winter Olympics, snow is expected during the final day of competition.
The "Beast from the East" will not only bring unusual late-February cold to the United Kingdom next week, but also several opportunities for disruptive snow.
Some of the same communities being threatened by severe weather this weekend may face more violent thunderstorms and flooding as February comes to a close.
A storm sweeping through the northeastern United States will bring snow and ice to parts of New England as heavy rain elevates the risk of flooding farther south.
As the start of the Major League Baseball regular season approaches, teams have headed to Florida and Arizona for spring training.