A Russian scientist over the weekend dismissed the claims of his colleagues that water pulled from a lake buried for millions of years beneath Antarctica contained a strange new form of microbial life.

But on Monday, those colleagues insisted that the bacterium they have discovered doesn't fall into any known categories.

The tiny creature in question came from a sample of water pulled by a team of Russian scientists from lake Vostok in February, 2012, after more than two decades of drilling, a major achievement hailed by scientists around the world. Vostok likes buried beneath Antarctica and hasn't been exposed to air or light in millions of years. One goal of the dig was to see whether some strange creatures lurked in that darkness.


Such a life form could lead to insights as to what forms life might take on other planets, as well as adding to our knowledge of the varied shapes organisms take here on Earth. On Thursday, Sergei Bulat, a researcher at the Laboratory of Eukaryote Genetics at the St. Petersburg Nuclear Physics Institute, claimed victory.

More On This...

“After excluding all known contaminants … we discovered bacterial DNA that does not match any known species listed in global databanks. We call it unidentified and 'unclassified' life,” Bulat said, according to a story on Russian news wire Ria Novosti.

But on Saturday, Eukaryote genetics laboratory head Vladimir Korolyov told the Interfax news agency that they did not find any life forms -- just contaminants that remained from the drilling process.

"We found certain specimen, although not many, but all of them belonged to contaminants (microorganisms from the bore-hole kerosene, human bodies or the lab). There was one strain of bacteria which we did not find in drilling liquid, but the bacteria could in principal use kerosene as an energy source," Korolyov said.

"That is why we can't say that a previously-unknown bacteria was found," he added.

Still, Bulat and his colleague Valery Lukin insisted to the Associated Press that the bacterium has no relation to any of the existing types, though extensive research of the microbe that was sealed under the ice for millions of years will be necessary to prove the find and determine the bacterium's characteristics.

Bulat and Lukin said that the small size of the initial sample and its heavy contamination made it difficult to conduct more extensive research. They voiced hope that the new samples of clean frozen water that are to arrive in St. Petersburg this spring will make it possible to "confirm the find and, perhaps, discover new previously unknown forms of microbial life."

"Deepwater devices designed at our institute will be used next year for taking pure water with pure samplers," they said.

A U.S. team that recently touched the surface of Lake Whillans, a shallower subglacial body of water west of the South Pole, also found microbes. The scientists are yet to determine what forms of bacteria they found.

The Associated Press contributed to this report.