The news of a bacterial life form that not only resists the toxic effects of arsenate but has been reported to use arsenate in place of phosphate has reverberated around the scientific world.  If the reported results are to be believed, then plainly this is a very significant find. (I haven’t been to the local library to read the Science article myself and I’m too cheap to pay for a download!)

From the reviews I have read, the paper reports the presence of the Group V oxoanion arsenate in the organism.  But the presence of an arsenate as a functional group in a biomolecule apparently has not been substantiated. I think this has to happen before we break out the champagne. Arsenate linkages have to be made in vivo by enzymes in order to qualify this as a new kind of life form.  It would be nice to hear about a successful enzymatic emplacement of arsenate in a controlled experiment. So far, all we know is that the organism is extremely tolerant of arsenate.

12/10/10. UPDATE.  My my my. Now we’re starting to hear doubters chiming in on the news of arsenious life forms at Mono Lake. What is that flushing sound?? Could it be the sound of careers circling ’round the porcelain bowl on the way to pergatory?  Remember Pons and Fleischman.

Extraordinary claims require extraordinary evidence.   C. Sagan