(December 2, 2010 at 6:21 pm)orogenicman Wrote: I don't think this is an issue of multiple abiogenesis at all. All this means is that a bacterium living in an extreme environment has evolved to an extreme environment (albeit one that was rich in arsenic and poor in phosphorus). So, for instance, no one is proposing (certainly not based on any data I know of) that these bacteria first formed back in the primordial soup during Earth's early beginnings. What these results have shown is that some bacteria are capable of replacing phosphorus with arsenic, an ability which not only affects their DNA makeup, but also their ability to manufacture certain necessary energy compounds, such as ATP. Apparently, they were able to adapt by producing a different energy molecule that uses arsenic instead of phosphorus. I eagerly await results from others to see if these findings hold up, and to see what details are filled in.
I think you are right, since remnant phosphate groups are to be found in the organism's DNA.
