Rapid arsenite oxidation by Thermus aquaticus and Thermus thermophilus: Field and laboratory investigations

Thermus aquaticus and Thermus thermophilus, common inhabitants of terrestri al hot springs and thermally polluted domestic and industrial waters, have been found to rapidly oxidize arsenite to arsenate. Field investigations at a hot spring in Yellowstone National Park revealed conserved total arsenic transport and rapid arsenite oxidation occurring within the drainage chann el. This environment was heavily colonized by Thermus aquaticus. In laborat ory experiments, arsenite oxidation by cultures of Thermus aquaticus YT1 (p reviously isolated from Yellowstone National Park) and Thermus thermophilus HB8 was accelerated by a factor of over 100 relative to abiotic controls. Thermus aquaticus and Thermus thermophilus may therefore play a large and p reviously unrecognized role in determining arsenic speciation and bioavaila bility in thermal environments.