Colwellia, extreme life form

[Blob]

Even when it's cold enough to freeze the mercury in your thermometer, life goes on - the frigid wastes of the solar system never looked so habitable

In the icy expanse of the Arctic Ocean, a strange beast glides through the endless tunnels that honeycomb the floating sea ice. Propelled by a whip-like tail, it thrives at temperatures that would kill a human in minutes.
As winter approaches, the mercury drops and the sea ice hardens. Those tunnels of water close up and almost disappear. Temperatures plummet below -20 °C. But the whip-tailed beast, a bacterium called Colwellia 34H, remains alive and well, sealed in the ice in bubbles of briny liquid not much larger than its own single-celled body.
Colwellia used to be seen as a freak of nature, the hardiest of all cold-loving bugs. But biologists are starting to realise that it is not at all unusual. Wherever they look - in permafrost, icebergs, glaciers or ice caps - they find die-hard life forms whose appetite for enduring the cold simply astonishes.

Source


Title: Motility of Colwellia psychrerythraea Strain 34H at Subzero Temperatures
Authors: Karen Junge, Hajo Eicken, Jody W. Deming

We examined the Arctic bacterium Colwellia psychrerythraea strain 34H for motility at temperatures from 1 to 15°C by using transmitted-light microscopy in a temperature-controlled laboratory. The results, showing motility to 10°C, indicate much lower temperatures to be permissive of motility than previously reported (5°C), with implications for microbial activity in frozen environments.

Read more (PDF)

[AK]

Yep, I've seen em. Jody Deming is one of the members of our Astrobiology node here at UW...

[Dr Nigel]

I saw the article in the print edition of New Scientist. Very interesting. It holds out a little more hope that microbial life, at least, exists somewhere out there, in the cold places of the solar system...

[makaya325]

y dont people ever mention that even complex life like tubeworms and giant clams could exist in extreme enviorments.

[Dr Nigel]

y dont people ever mention that even complex life like tubeworms and giant clams could exist in extreme enviorments.

Mainly, I think, because simpler life forms are more hardy than more complex ones. By hardy, I don't just mean able to tolerate conditions that we would consider extreme. I also mean to include the ability to survive in a wide range of conditions.

The hardiest animals of which I am aware are tardigrades (water bears). They are tolearant of levels of radiation that would kill many other animals, and they can survive being treated to a fairly hard vacuum.

In terms of ability to survive, microbes win hands down (if you'll pardon that metaphor). Whether it is extremes of temperature, pressure, pH, salinity, there are bugs that can survive in it. There are not always higher organisms that can tolerate these extremes. Low temperature is a particular problem (ice crystals can be very damaging to cellular structure).