SolkaTruesilver wrote:Oh well. A new structure of life form is still interesting. I hope they really juice out this discovery and can create nifty stuff with it.
Tyyr wrote:At this point I think we'd probably be safest saying that so long as an energy source is present life is a possibility because it just keeps getting weirder.
Mikey wrote:What makes it weird (and wonderful) isn't that it needs arsenic instead of phosphorous... it's that this bacteria can use either depending on the environmental conditions.
When NASA announced the discovery of an arsenic-eating microbe in a California lake last week, the agency hailed it as a suggestion that life as we know it, well, isn't life as we know it.
"We have cracked open the door to what is possible for life elsewhere in the universe," Felisa Wolfe-Simon of the NASA Astrobiology Institute and U.S. Geological Survey, who led the study, said at a news conference.
NASA's team of astrobiologists had taken samples of the bacteria from mineral-dense Lake Mono -- in a volcanic region of Northern California near the Nevada border -- and starved them of phosphate, the meal of choice for most DNA-based organisms. Instead, the scientists force-fed the bacteria a form of arsenic, and, much to the researchers' surprise, the bacteria continued to grow and flourish on their new diet of poison.
But then other scientists began digging into the paper outlining NASA's research and findings, and they're now charging that the research behind it is flawed.
"I was outraged at how bad the science was," University of British Columbia microbiology professor Rosie Redfield told Slate's Carl Zimmer. Redfield also posted a scathing critique of the report on her blog.
Redfield and other detractors point out that when NASA scientists removed the DNA from the bacteria for examination, they didn't take the steps necessary to wash away other types of molecules. That means, according to the critics, that the arsenic may have merely clung to the bacteria's DNA for a ride without becoming truly ingrained into it.
The report's detractors also note that the NASA scientists fed the bacteria salts that contained trace amounts of phosphate, so it's possible that the bacteria were able to survive on those tiny helpings of phosphate instead of the arsenic.
"This paper should not have been published," University of Colorado molecular biology professor Shelley Copley told Slate's Zimmer.
So why would NASA scientists make such a big deal out of a discovery that, according to critics, they must have suspected was questionable?
"I suspect that NASA may be so desperate for a positive story that they didn't look for any serious advice from DNA or even microbiology people," UC-Davis biology professor John Roth told Zimmer.
A NASA spokesperson brushed off the criticism. The paper's authors have not responded to the firestorm. Needless to say, that posture, too, has drawn the ire of critics. "That's kind of sleazy given how they cooperated with all the media hype before the paper was published," Redfield said.
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