Bio-reduction of selenite to elemental red selenium by Tetrathiobacter kashmirensis.
A bacterium that detoxifies selenite by reduction to insoluble elemental red selenium was isolated from soil. The strain showed an unusually high resistance to the toxic effects of selenite by growing in media containing 64 mM selenite. 16S rRNA gene sequence alignment identified the isolate as Tetrathiobacter kashmirensis. Fatty acid analysis and morphology confirmed the identification. The isolate reduced selenite to elemental selenium under aerobic conditions only. Native gel electrophoresis of cell-free extracts revealed a band, corresponding to a molecular weight of approximately 120 kDa, that reduced selenite. In culture, the strain did not reduce selenate; however, a soluble and inducible enzyme with a molecular weight of approximately 90 kDa that reduced both selenate and nitrate was present in cell-free extracts. This organism might be useful in bioreactors designed to remove selenite from contaminated water.
Hunter
William J
WJ
USDA-ARS, Fort Collins, CO 80526-8119, USA. william.hunter@ars.usda.gov
Manter
Daniel K
DK
D042401:Alcaligenaceae / Q000145:classification / Q000254:growth & development / Q000302:isolation & purification* / Q000378:metabolism*; D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism; D004269:DNA, Bacterial / Q000235:genetics; D004275:DNA, Ribosomal / Q000235:genetics; D008969:Molecular Sequence Data; D009573:Nitrites / Q000378:metabolism; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000737:chemistry / Q000378:metabolism; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012643:Selenium / Q000378:metabolism*; D018038:Sodium Selenite / Q000378:metabolism*; D012988:Soil Microbiology
D001426:Bacterial Proteins; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D009573:Nitrites; D012336:RNA, Ribosomal, 16S; D010088:Oxidoreductases; C078108:selenate reductase; D012643:Selenium; D018038:Sodium Selenite