title: Characterization of technetium(vII) reduction by cell suspensions of thermophilic bacteria and archaea.
abstract: Washed cell suspensions of the anaerobic hyperthermophilic archaea Thermococcus pacificus and Thermoproteus uzoniensis and the anaerobic thermophilic gram-positive bacteria Thermoterrabacterium ferrireducens and Tepidibacter thalassicus reduced technetium [(99)Tc(VII)], supplied as soluble pertechnetate with molecular hydrogen as an electron donor, forming highly insoluble Tc(IV)-containing grayish-black precipitate. Apart from molecular hydrogen, T. ferrireducens reduced Tc(VII) with lactate, glycerol, and yeast extract as electron donors, and T. thalassicus reduced it with peptone. Scanning electron microscopy and X-ray microanalysis of cell suspensions of T. ferrireducens showed the presence of Tc-containing particles attached to the surfaces of non-lysed cells. This is the first report on the reduction in Tc(VII) by thermophilic microorganisms of the domain Bacteria and by archaea of the phylum Euryarchaeota.
authors.affiliation: Winogradsky Institute of Microbiology, Russian Academy of Sciences, Prospect 60-letiya Oktyabrya 7/2, 117312 Moscow, Russia.
authors.forename: Nikolay A
authors.initials: NA
authors.lastname: Chernyh
authors.forename: Sergei N
authors.initials: SN
authors.lastname: Gavrilov
authors.forename: Vladimir V
authors.initials: VV
authors.lastname: Sorokin
authors.forename: Konstantin E
authors.initials: KE
authors.lastname: German
authors.forename: Claire
authors.initials: C
authors.lastname: Sergeant
authors.forename: Monique
authors.initials: M
authors.lastname: Simonoff
authors.forename: Frank
authors.initials: F
authors.lastname: Robb
authors.forename: Alexander I
authors.initials: AI
authors.lastname: Slobodkin
mesh_terms: D001105:Archaea / Q000378:metabolism*; D001419:Bacteria / Q000378:metabolism*; D010084:Oxidation-Reduction; D013667:Technetium / Q000378:metabolism*
chemical_list: D013667:Technetium