title: Hexavalent chromium reduction by an actinobacterium Flexivirga alba ST13T in the family Dermacoccaceae.
abstract: An isolated strain Flexivirga alba ST13(T) was examined for the reducing activity of hexavalent chromium (Cr(VI)). Strain ST13(T) grew in the liquid medium containing 0.33 mM Cr(VI) under aerobic cultivation, even though growth was inhibited on agar minimal media containing 0.31 mM Cr(VI). The growth in the liquid medium containing Cr(VI) at 3 mM was severely inhibited, and the concentration of Cr(VI) decreased below the detection limit within 13 days. Most of the Cr(VI) was eliminated from the liquid medium in the log phase and the stationary phase. XANES analysis of the precipitate shows the presence of Cr(OH)(3), indicating the bacterial reduction of Cr(VI) to trivalent chromium (Cr(III)). The bacterial Cr(VI) reduction was more efficient in minimal medium supplemented with molasses than with glucose. These results strongly suggest that the isolate F. alba ST13(T) is a novel actinobacterium with Cr(VI) reducing activity that is stimulated by molasses.
authors.affiliation: Graduate School of Bionics, Tokyo University of Technology, 1401-1 Katakura-machi, Hachioji, Tokyo 192-0982, Japan. tsugiyama@bs.teu.ac.jp
authors.forename: Tomoyasu
authors.initials: T
authors.lastname: Sugiyama
authors.forename: Hironori
authors.initials: H
authors.lastname: Sugito
authors.forename: Kho
authors.initials: K
authors.lastname: Mamiya
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Suzuki
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Ando
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Ohnuki
mesh_terms: D000192:Actinomycetales / Q000378:metabolism*; D002840:Chromates / Q000378:metabolism; D002857:Chromium / Q000378:metabolism*; D003470:Culture Media / Q000378:metabolism; D008965:Molasses; D010084:Oxidation-Reduction; D013997:Time Factors
chemical_list: D002840:Chromates; D003470:Culture Media; D002857:Chromium; C074702:chromium hexavalent ion