title: One- and two-electron oxidation of reduced glutathione by peroxidases.
abstract: The oxidation of glutathione by horseradish peroxidase 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 glutathione disulfide without forming a thiyl radical intermediate, except in the presence of the thiyl radical-generating horseradish peroxidase.
mesh_terms: D003497:Cyclic N-Oxides / Q000378:metabolism; D004578:Electron Spin Resonance Spectroscopy; D005609:Free Radicals; D005978:Glutathione / Q000031:analogs & derivatives / Q000096:biosynthesis / Q000378:metabolism*; D019803:Glutathione Disulfide; D006735:Horseradish Peroxidase / Q000378:metabolism*; D010084:Oxidation-Reduction; D010101:Oxygen Consumption; D010544:Peroxidases / Q000378:metabolism*
chemical_list: D003497:Cyclic N-Oxides; D005609:Free Radicals; C017245:5,5-dimethyl-1-pyrroline-1-oxide; D006735:Horseradish Peroxidase; D010544:Peroxidases; D005978:Glutathione; D019803:Glutathione Disulfide