title: One- and two-electron oxidation of reduced glutathione by peroxidases.
abstract: The oxidation of glutathione by horseradish peroxidase or lactoperoxidase forms a thiyl free radical, as demonstrated with the spin-trapping ESR technique. Reactions of this thiyl free radical result in oxygen consumption, which is inhibited by the radical trap 5,5-dimethyl-1-pyrroline-N-oxide. In contrast to L-cysteine oxidation, glutathione oxidation is highly hydrogen peroxide-dependent. The oxidation of glutathione by glutathione peroxidase forms GSSG without forming a thiyl radical intermediate except in the presence of the thiyl radical-generating horseradish peroxidase.
mesh_terms: D002374:Catalase / Q000378:metabolism; D004578:Electron Spin Resonance Spectroscopy / Q000379:methods; D004583:Electrons; D005978:Glutathione / Q000031:analogs & derivatives* / Q000378:metabolism; D019803:Glutathione Disulfide; D005979:Glutathione Peroxidase / Q000378:metabolism*; D006735:Horseradish Peroxidase / Q000378:metabolism*; D007700:Kinetics; D007784:Lactoperoxidase / Q000378:metabolism*; D010084:Oxidation-Reduction; D010101:Oxygen Consumption; D010544:Peroxidases / Q000378:metabolism*
chemical_list: D006735:Horseradish Peroxidase; D007784:Lactoperoxidase; D010544:Peroxidases; D002374:Catalase; D005979:Glutathione Peroxidase; D005978:Glutathione; D019803:Glutathione Disulfide