Sunday, January 16, 2011

Bacteria survive 34,000 years in salt crystals

34,000-year-old organisms found buried alive Scientists bring back ancient salt crystals, dug up from deep below Death Valley for climate research. The sparkling crystals are carefully packed away until, years later, a young, unknown researcher takes a second look at the 34,000-year-old crystals and discovers, trapped inside, something strange... 'It was actually a very big surprise to me, said Brian Schubert, who discovered ancient bacteria living within tiny, fluid-filled chambers inside the salt crystals...

Salt crystals grow very quickly, imprisoning whatever happens to be floating -- or living -- nearby inside tiny bubbles just a few microns across... Research indicates this process occurs in modern saline lakes... The new findings, along with details of Schubert's work, are published in the January 2011 edition of GSA Today, the publication of the Geological Society of America.

Schubert, now an assistant researcher at the University of Hawaii, said the bacteria -- a salt-loving sort still found on Earth today -- were shrunken and small, and suspended in a kind of hibernation state. 'They're alive, but they're not using any energy to swim around, they're not reproducing... 'They're not doing anything at all except maintaining themselves.'

The key to the microbes' millennia-long survival may be their fellow captives -- algae, of a group called Dunaliella. 'The most exciting part to me was when we were able to identify the Dunaliella cells in there,' Schubert said, 'because there were hints that could be a food source.'... These tiny chambers could house entire, microscopic ecosystems...

The next step for researchers is to figure out how the microbes, suspended in a starvation-survival mode for so many thousands of years, managed to stay viable. 'We're not sure what's going on,' Lowenstein said. 'They need to be able to repair DNA, because DNA degrades with time.' Schubert said the microbes took about two-and-a-half months to 'wake up' out of their survival state before they started to reproduce.
Image source here.