HR: 1340h
AN: B33C-1439    [Abstracts]
TI: Isolation of Strain MLTeJB From Mono Lake, California, a Dissimilatory Tellurite Respiring Prokaryote.
AU: * Baesman, S M
EM: sbaesman@usgs.gov
AF: U.S. Geological Survey, 345 Middlefield Road, Menlo Park, CA 94025, United States
AU: Oremland, R S
EM: roremlan@usgs.gov
AF: U.S. Geological Survey, 345 Middlefield Road, Menlo Park, CA 94025, United States
AB: Previous investigations on the dissimilatory reduction of Te-oxyanions have been constrained by the inhibtory effects of circa 1.0 mM concentrations of either Te(IV) or Te(VI) upon growth of established cultures. Therefore we initiated new enrichments using anoxic Mono Lake mud supplemented with 10 mM Te(IV) as the electron acceptor and lactate as the electron donor. Sediments turned black with time owing to the formation of Te(0), microscopic examination of which confirmed the presence of both shards, rosettes, and nanospheres of Te(0). The enrichment was subcultured several times in liquid medium and then streaked onto solid medium and incubated in an anaerobic chamber. Isolated black colonies were re-streaked several times, and thence inoculated into liquid medium. However, growth in liquid medium required the presence of a small amount of solid phase, which included a plug of either agar, phytagel, or glass beads. Growth resulted in oxidation of lactate to acetate, formate and CO2 with the reduction of Te(IV) to Te(0). The isolate, strain MLTeJB was a non-motile rod that stained Gram positive, and formed copious exogenous deposits of Te(0) nano-shards and rosettes. Further details on the physiology of this organism will be presented.
DE: 0419 Biomineralization
DE: 0448 Geomicrobiology
DE: 0456 Life in extreme environments
DE: 0463 Microbe/mineral interactions
DE: 0471 Oxidation/reduction reactions (4851)
SC: Biogeosciences [B]
MN: 2007 Fall Meeting