title: The action of free radicals on Deinococcus radiodurans carotenoids.
abstract: The possible role of carotenoids as free radical scavengers has not been completely elucidated. To gain further insight into the quenching of OH radicals by carotenoids, we used a feasible bacterial model, Deinococcus radiodurans, a red pigmented bacterium. We compared the action of H2O2 which produces in vivo OH radicals by a Fenton-type reaction on the parental and two mutant strains, i.e., a red pigmented and a colorless one. While the red pigmented bacteria were resistant to H2O2 action, the colorless strain was significantly more sensitive and its sensitivity was dose-dependent. In the red pigmented strains, H2O2 induced a significant decrease in one carotenoid (X5), which could be responsible for the antioxidant activity.
authors.affiliation: Laboratoire de Biochimie Médicale A, Bordeaux, France.
authors.forename: M A
authors.initials: MA
authors.lastname: Carbonneau
authors.forename: A M
authors.initials: AM
authors.lastname: Melin
authors.forename: A
authors.initials: A
authors.lastname: Perromat
authors.forename: M
authors.initials: M
authors.lastname: Clerc
mesh_terms: D002338:Carotenoids / Q000302:isolation & purification / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D003676:Deferoxamine / Q000494:pharmacology; D005609:Free Radicals; D006094:Gram-Positive Bacteria / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D007700:Kinetics; D009154:Mutation; D013045:Species Specificity
chemical_list: D005609:Free Radicals; D002338:Carotenoids; D006861:Hydrogen Peroxide; D003676:Deferoxamine