Back in December 2010, there was a press conference held by NASA to announce the discovery of a bacterium found in a high salt, high pH lake with high concentrations of arsenic that seemed to have substituted arsenic for phosphorus in the bacterium’s biomolecules. This set off a wave of response in the blogosphere regarding what Felisa Wolfe-Simon and her team did nor did not do to confirm arsenic was incorporated into DNA molecules. Controversy ranged from the ability of arsenic to form a stable compound to the types of experiments conducted to confirm incorporation of arsenic into molecules like DNA.

Wolfe-Simon et al. stated they would address all critiques of the Science paper if the critiques were also subject to peer review like their paper titled “A Bacterium That Can Grow by Using Arsenic Instead of Phosphorus”. On May 27, Science published eight Letters to the Editor and the Wolfe-Simon et al. response to the critical comments. Continue reading “Minding the As and P: Can Arsenic Substitute for Phosphorus or Not?”