title: Vitamins C and E donate single hydrogen atoms in vivo.
abstract: The antioxidant vitamins, C and E, eliminate cytotoxic free radicals by redox cycling. Energetic and kinetic considerations suggest that cycling of vitamin C and vitamin E between their reduced and free radical forms occurs via the transfer of single hydrogen atoms rather than via separate electron transfer and protonation reactions. This may enable these vitamins to reduce many of the damaging free radicals commonly encountered by biological systems while minimizing the reduction of molecular oxygen to superoxide.
authors.affiliation: Department of Biological Sciences, Wayne State University, Detroit, MI 48202.
authors.forename: D
authors.initials: D
authors.lastname: Njus
authors.forename: P M
authors.initials: PM
authors.lastname: Kelley
mesh_terms: D001205:Ascorbic Acid / Q000378:metabolism*; D004579:Electron Transport; D016166:Free Radical Scavengers; D005609:Free Radicals; D007700:Kinetics; D010084:Oxidation-Reduction; D011522:Protons; D013481:Superoxides / Q000378:metabolism; D014810:Vitamin E / Q000378:metabolism*
chemical_list: D016166:Free Radical Scavengers; D005609:Free Radicals; D011522:Protons; D013481:Superoxides; D014810:Vitamin E; D001205:Ascorbic Acid