March 11, 2013
Scientists Find Bacteria Discovery In Antarctic Lake Was A Contaminant
Lawrence LeBlond for redOrbit.com - Your Universe Online
Last Friday (Mar 8) headlines popped up everywhere reporting that Russian scientists had found initial evidence of a new bacterial life form pulled up from the depths of Antarctica´s largest subglacial body of water, Lake Vostok. The discovery was viewed as extraordinary, and may have sealed the deal for Russia becoming the first country to discover a new species of bacteria in such an extreme location.
Vladimir Korolyov, head of the Laboratory of Eukaryote Genetics at the St. Petersburg Nuclear Physics Institute (PNPI), said the organism, which was claimed to come from a sample pulled up from the lake in February 2012, did not come from the lake as previously mentioned.
“We can't say that a previously-unknown bacteria was found,” said Korolyov.
The initial claim was made by Russian scientist Sergei Bulat of PNPI. He told state-owned RIA Novosti news agency on Thursday (Mar 7) that 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.”
But Korolyov on Saturday (Mar 9) told Interfax news agency that they had in fact not found any new life forms — just contaminant from the fluid used in the drilling process.
Concerns were raised that the drilling process could have led to contamination, but Bulat maintained the technology that was utilized to keep the lake from being polluted also meant scientists would be retrieving clean and unspoiled water samples. He added that researchers separated out species of bacteria known to exist in the drilling fluid to ensure there would be no cross-contamination.
However, Korolyov said that after further analysis of the specimens in the lab samples, scientists determined that all of the specimens found “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.”
Still, scientists are keeping their fingers crossed on a new batch of samples that are expected to return in May, from a second round of drilling that took place earlier this year at the Lake Vostok drill site.
Korolyov told Interfax that next year when scientists return to Lake Vostok, they will be utilizing new deep-water devices specially designed in the Eukaryote lab for “taking pure water with pure samplers."
If any life exists in the deep, dark, cold abyss of Lake Vostok, it will likely be found only when scientists can utilize the proper tools to ensure non-contamination is occurring.