December 16, 2010

Critics Skeptical Over Bacteria Thriving On Arsenic

NASA-funded researchers announced earlier this month that they had found a new life form that thrives on arsenic, but critics are skeptical of the new outlook.

"I don't know whether the authors are just bad scientists or whether they're unscrupulously pushing NASA's 'There's life in outer space!' agenda," wrote Canadian microbiologist Rosie Redfield in a blog that ignited the web furor.  

Criticism spread, sparking a wide debate over what is in the alleged arsenic-eater's DNA.

Scientists are waiting to obtain samples of the same bacteria to try and replicate the findings that Felisa Wolfe-Simon, along with colleagues, published December 2nd in the journal Science.

The journal's editors have "received about 20 technical comments and letters responding to the article," the magazine said in a statement sent to AFP on Tuesday.

"Responses will undergo review, and Wolfe-Simon's team will then be asked to formally address their peers' questions in a future edition of Science," it said.

"It is hoped that the paper-responses and the authors' replies can be published in January 2011."

Wolfe-Simon posted a statement on her website saying that she and her colleagues "welcome lively debate."

"My research team and I are aware that our peer-reviewed Science article has generated some technical questions and challenges from within the scientific community," she wrote.

"Our manuscript was thoroughly reviewed and accepted for publication by Science; we presented our data and results and drew our conclusions based on what we showed. But we welcome lively debate since we recognize that scholarly discourse moves science forward."

She said that she and her colleagues were working on a list of "frequently asked questions to help promote general understanding of our work."

Another blogger said that there were potential errors, including that the DNA the researchers said was built with arsenic actually contained phosphate.

"There's been a lot of hype around the news of GFAJ-1, the microbe claimed to substitute arsenate for phosphate in its DNA," wrote scientist Alex Bradley on blog We Beasties.

"In particular, one subtle but critical piece of evidence has been overlooked, and it demonstrates that the DNA in question actually has a phosphate -- not an arsenate -- backbone."

Various media sites like Wired, Slate, ABC News and The Observatory have all carried versions of the story.

"The controversy surrounding this organism is quite fascinating," Peter Gilligan, a professor of Microbiology-Immunology at the University of North Carolina told AFP in an email.

"First, the work was published in one of the most prestigious peer reviewed journals, Science. A sharp rebuttal that was peer reviewed by no one appears in a blog written Rosie Redfield," he wrote.

"What I find fascinating as a journal editor and senior scientist is how information can be disseminated so quickly globally and how at least in some quarters it seems, that peer reviewed information and blogging can be given equal weight," he added.

"It remains to be seen who will be proven to be correct."

Gilligan told AFP that from his prospective, Wolfe-Simon "maintained the high ground in this controversy by offering the organisms she has studied to other investigators via the typical channels."

Heather Olin, who writes for We Beasties, told AFP that she did not "know of anyone currently working on replicating the Wolfe-Simon findings," though she was aware that "many people have requested the strain of bacteria from Wolfe-Simon so that they can begin to do that type of work."

"However, these things tend to move slowly, and it is hard to know when that will happen," she said.


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