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No, arsenic is not a life-giver

A 2010 NASA study that suggested a bacterium could thrive on arsenic instead of phosphorus is refuted by two new pieces of research.

Mono Lake, where the 2010 bacterium was found. Periodic Videos/YouTube Screenshot: Chris Matyszczyk/CNET

I confess to not having been aware that arsenic might breathe life into things.

I had only been aware of it as something killers use in Agatha Christie novels.

However, in 2010, a researcher declared that a bacterium in California's Mono Lake (near Yosemite) thrived on arsenic, while being deprived of phosphorus. (I have embedded a discussion of this finding.)

At the time, Felisa Wolfe-Simon of NASA's Astrobiology Institute suggested that life as we know it may not be life as we know it.

Now, however, two new studies suggest that it may be life as we know it, after all. It appears that carbon, hydrogen, oxygen, nitrogen, sulfur, and phosphorus are all we've got.

In examining the fascinating bacterium in question, GFAJ-1, two different sets of researchers concluded that it was phosphate-dependent after all.

PopSci reports that though arsenic is, indeed, not so distant chemically from phosphorus, these studies showed that it isn't some new, enthralling life-giver.

In Wolfe-Simon's work, she had noted that the bacterium did include some phosphates, but concluded that it was in amounts far too small to sustain life.

Science -- which published both Wolfe-Simon's work and the new work from Tobias Erb and colleagues at Institute of Microbiology at ETH Zurich and a team led by Marshall Reaves at Princeton University -- issued a definitive statement: "The new research shows that GFAJ-1 does not break the long-held rules of life, contrary to how Wolfe-Simon had interpreted her group's data."

Wolfe-Simon appears not to wish her work poisoned.

She told PopSci that it was still conceivable that there might be arsenate metabolites that do somehow help certain organisms survive.

Still, we can probably all go back to Pinning our favorite pictures of table lamps and landscaping, without worrying about whether arsenic might be good for us or whether there is alien matter in Yosemite.