- 03 Dec 10, 01:28#228402Mono Lake was selected as a work site by Wolfe-Simon because it is highly unusual and had been well studied by other scientists trying to answer different questions.
The lake receives run-off from the Sierra Nevada mountains, which have relatively high concentrations of arsenic. When the water arrives at Mono Lake, it has nowhere to go because there are no rivers carrying water further downstream. That means the arsenic, and other elements and compounds, can concentrate to unusally high levels. Arsenic is present in Mono Lake at a concentration 700 times greater than what the EPA considers safe.
Wolfe-Simon was invited to use the Menlo Park, Calif., lab of the U.S. Geological Survey and was aided in her work by senior research scientist Ron Oremland, who has studied arsenic in Mono Lake for decades. The initial work was quite simple: She took mud from the briny as well as toxic lake into the lab and began growing bacteria in Petri dishes. She gradually replaced phosphate salt with arsenic until the surviving bacteria could grow without needing the phosphates at all.
The bugs, an otherwise common bacteria in the halomonadaceae family, thrived without phosphates and with lots of arsenic. She then determined that the arsenic was embedded in the core genetic and energy transfer systems of the bacteria - that it appeared to have replaced (or preceeded) the phosphorus.
As she explained, replacing phosphorus with arsenic may seem suicidal, but the two are very similar in their makeup. Arsenic is considered toxic because most living things take it in and treat it like phosphorus, only to be destroyed by the small differences.
She said that while small amounts of the phosphorus remained in the arsenic-based bugs, she was able to determine that it was definitely not enough to supply the presumed phosphorus needs of the cell. That, she said, was being done with the arsenic.
"Sometimes I'm asked why something like this has never been found before, and the answer is that nobody has run the experiment before," Wolfe-Simon said. "There was nothing really complicated about it - I asked a simple question that was testable and got an answer."
Wolfe-Simon said she hopes to further test her findings in northern Argentina, where, she's been told, some microbes can not only tolerate arsenic, but absolutely need arsenic to survive.
Le coeur a ses raisons que la raison ne connaît point. 
. Not too say this is not significant as my meaning is more towards a 'world changing' discovery or a step forward for mankind that could not,would not nor has not been realized or accepted until it actually happens.
Footprints will be Chinese
- By hass25