Friday, October 20, 2006
Researchers have discovered an isolated, self-sustaining, bacterial community living under extreme conditions almost two miles deep beneath the surface in a South African gold mine. It is the first microbial community demonstrated to be exclusively dependent on geologically produced sulfur and hydrogen and one of the few ecosystems found on Earth that does not depend on energy from the Sun in any way. The discovery, appearing in the October 20 issue of the journal Science, raises the possibility that similar bacteria could live beneath the surface of other worlds, such as Mars or Jupiter's moon Europa.
"These bacteria are truly unique, in the purest sense of the word," said lead author Li-Hung Lin (homepage), now at National Taiwan University, who performed many of the analyses as a doctoral student at Princeton and as a postdoctoral researcher at the Carnegie Institution's Geophysical Laboratory.
As Lin explained: "We know how isolated the bacteria have been because our analyses show that the water they live in is very old and hasn't been diluted by surface water. In addition, we found that the hydrocarbons in the local environment did not come from living organisms, as is usual, and that the source of the hydrogen (H2) needed for their respiration comes from the decomposition of water (H2O) by radioactive decay of uranium, thorium, and potassium."
Continued at "Otherworldly bacteria that use radiated water for food discovered two miles down"
Based on "Long-Term Sustainability of a High-Energy, Low-Diversity Crustal Biome" (Abstract)
[Microbes, Evolution, Research, Extremophiles, Africa, Geology, Sulphur, Ecosystem]
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