Characterization of technetium(vII) reduction by cell suspensions of thermophilic bacteria and archaea.
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.
Chernyh
Nikolay A
NA
Winogradsky Institute of Microbiology, Russian Academy of Sciences, Prospect 60-letiya Oktyabrya 7/2, 117312 Moscow, Russia.
Gavrilov
Sergei N
SN
Sorokin
Vladimir V
VV
German
Konstantin E
KE
Sergeant
Claire
C
Simonoff
Monique
M
Robb
Frank
F
Slobodkin
Alexander I
AI
D001105:Archaea / Q000378:metabolism*; D001419:Bacteria / Q000378:metabolism*; D010084:Oxidation-Reduction; D013667:Technetium / Q000378:metabolism*
D013667:Technetium