Thursday, November 23, 2006

Scientists have found out the closed community of the bacteria living on depth of 2,8 kilometers under the ground. Until recently they have been absolutely isolated from a surface and as has appeared, relied on uranium ores as an energy source for a life.

This opening have made by Tullis Onstott from university of Princeton, Liza Pratt from university of Indiana in Bloomington (Indiana University, Bloomington) and a lot of other authors from the several scientific organizations of the USA, Canada, Taiwan and Germany.

"The rocky bark of the Earth actually is not experienced on depths more 1km below a surface. Organisms which we describe in this work, live in completely different world, in comparison with what we know on a surface ", - Liza Pratt speaks.

At once we shall tell: bacteria which live in the subsoil waters exuding from the big depth, or in others environments, - not news. However till now remains to unknown persons, whether these underground microorganisms have been rather recently brought from a surface and now die out, or they - old and permanent residents of so unusual inhabitancy.

However, opening of last years have forced biologists to reconsider representations about an opportunity of a life in the most improbable conditions.

It is enough to recollect almost immortal bacteria which live in the breed laying on 800 meters below a level of a bottom of ocean, the surprising photosynthetic bacterium living near of geothermal sources on ocean bottom where there is no sunlight, and also - bacteria of lake the East.

Now the history of deep communities has received interesting continuation. Authors of work researched new, filled water, a break on one of gold mines about Johannesburg. 54 days they sampled some the water filtered mine from the big depth.

The analysis of DNA has shown presence at tests of water of several kinds of bacteria among which the new kind dominated over department Firmicutes.

It is necessary to tell, not the first opening of bacteria in mines of the republic of South Africa - in 2002 we informed it on the same find. But, first, beginners live even more deeply, than those bacteria that has been found earlier, and secondly (and this main thing) - new work of researchers has slightly opened a veil of secret above a source of their food.

Scientists have found out, that in the closed underground environment of bacterium Firmicutes play the same role, that on a surface play photosynthesizing organisms. They acquire a certain primary energy to give it further to all members of community.

On a surface as the primary source of energy for all alive we see beams of the Sun. Plants accumulate the weight due to photosynthesis, animals eat plants and so on.

And here under the ground, authors of work confirm, as a primary energy source radiation of uranium ores serves. It splits water into hydrogen and oxygen, and also promotes formation of sulfates from minerals containing sulfur.

And, as has shown research, that new kind Firmicutes, that scientists have found in a break, uses for the feed a combination of hydrogen and sulfates, and waste of ability to live of this bacterium already are a source of food for other microorganisms of the given break.

The analysis of age of a break in a combination to the genetic analysis of bacteria have shown, that they completely have been isolated from the ground relatives from 3 up to 25 million years ago.

But as superficial bacteria have got there for the first time as have adapted and have managed to colonize the area laying so deeply within the limits of a bark of the Earth, - remains secret.


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