title: Interaction between uranium and the cytochrome c3 of Desulfovibrio desulfuricans strain G20.
abstract: Cytochrome c(3) of Desulfovibrio desulfuricans strain G20 is an electron carrier for uranium (VI) reduction. When D. desulfuricans G20 was grown in medium containing a non-lethal concentration of uranyl acetate (1 mM), the rate at which the cells reduced U(VI) was decreased compared to cells grown in the absence of uranium. Western analysis did not detect cytochrome c(3) in periplasmic extracts from cells grown in the presence of uranium. The expression of this predominant tetraheme cytochrome was not detectably altered by uranium during growth of the cells as monitored through a translational fusion of the gene encoding cytochrome c(3) ( cycA) to lacZ. Instead, cytochrome c(3) protein was found tightly associated with insoluble U(IV), uraninite, after the periplasmic contents of cells were harvested by a pH shift. The association of cytochrome c(3) with U(IV) was interpreted to be non-specific, since pure cytochrome c(3) adsorbed to other insoluble metal oxides, including cupric oxide (CuO), ferric oxide (Fe(2)O(3)), and commercially available U(IV) oxide.
authors.affiliation: Department of Biochemistry, University of Missouri-Columbia, Columbia, MO 65211, USA.
authors.forename: Rayford B
authors.initials: RB
authors.lastname: Payne
authors.forename: Laurence
authors.initials: L
authors.lastname: Casalot
authors.forename: Tessa
authors.initials: T
authors.lastname: Rivere
authors.forename: Jeffrey H
authors.initials: JH
authors.lastname: Terry
authors.forename: Lise
authors.initials: L
authors.lastname: Larsen
authors.forename: Barbara J
authors.initials: BJ
authors.lastname: Giles
authors.forename: Judy D
authors.initials: JD
authors.lastname: Wall
mesh_terms: D000327:Adsorption; D019677:Artificial Gene Fusion; D003300:Copper / Q000737:chemistry; D003574:Cytochrome c Group / Q000235:genetics / Q000378:metabolism*; D045285:Desulfovibrio desulfuricans / Q000378:metabolism*; D005290:Ferric Compounds / Q000737:chemistry; D015964:Gene Expression Regulation, Bacterial; D017930:Genes, Reporter; D007763:Lac Operon / Q000235:genetics / Q000502:physiology; D010084:Oxidation-Reduction; D019897:Periplasm / Q000737:chemistry; D033903:Periplasmic Proteins / Q000032:analysis; D012329:RNA, Bacterial / Q000032:analysis; D012333:RNA, Messenger / Q000032:analysis; D014158:Transcription, Genetic; D014501:Uranium / Q000378:metabolism*; D017974:Uranium Compounds / Q000737:chemistry; D001616:beta-Galactosidase / Q000235:genetics / Q000378:metabolism
chemical_list: D003574:Cytochrome c Group; D005290:Ferric Compounds; D033903:Periplasmic Proteins; D012329:RNA, Bacterial; D012333:RNA, Messenger; D017974:Uranium Compounds; C000499:ferric oxide; D014501:Uranium; D003300:Copper; C017165:cytochrome c(3); D001616:beta-Galactosidase; C047385:uranium oxide; C030973:cupric oxide