spacetoday.net: New studies refute earlier arsenic life claims

Posted: Tue, Jul 10, 2012, 6:49 AM ET (1049 GMT)
Two studies released late Sunday refute earlier claims by NASA-funded researchers of the discovery of a bacterium that could thrive on arsenic instead of phosphorous. The original study, published in December 2010, found that a bacterium called GFAJ-1, found in California's Mono Lake, was able to substitute arsenic for phosphorous in its DNA. The finding was hailed at the time by NASA as a significant one in astrobiology, broadening the conditions where life could exist. But two papers released by the journal Science, which published the original finding, Sunday night were unable to replicate the original finding, concluding that GFAJ-1 could survive in the presence of arsenic but not incorporate it into its DNA or other elements. The journal itself concluded that the new studies refuted the original finding, although NASA officials, in a statement, said the situation called for additional research.