title: Effects of tetrahydropterines on the generation of quinones catalyzed by tyrosinase.
abstract: Tetrahydrobiopterine (6BH(4)) can diminish the oxidative stress undergone by keratinocytes and melanocytes by reducing the o-quinones generated by the oxidation of the corresponding o-diphenols. We found that 6BH(4) and their analogs reduced all the o-quinones studied. The formal potentials of different quinone/diphenol pairs indicate that the o-quinones with withdrawing groups are more potent oxidants than those with donating groups.
authors.affiliation: Department of Biochemistry and Molecular Biology A, Faculty of Biology, University of Murcia, Murcia, Spain.
authors.forename: Francis
authors.initials: F
authors.lastname: Garcia-Molina
authors.forename: Joseph Louis
authors.initials: JL
authors.lastname: Munoz-Munoz
authors.forename: Francis
authors.initials: F
authors.lastname: Martinez-Ortiz
authors.forename: Joseph
authors.initials: J
authors.lastname: Tudela
authors.forename: Francis
authors.initials: F
authors.lastname: García-Cánovas
authors.forename: Joseph Neptune
authors.initials: JN
authors.lastname: Rodriguez-Lopez
mesh_terms: D016227:Benzoquinones / Q000378:metabolism*; D055162:Biocatalysis; D001708:Biopterins / Q000737:chemistry / Q000494:pharmacology; D014442:Monophenol Monooxygenase / Q000378:metabolism*; D010084:Oxidation-Reduction; D011622:Pterins / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D016227:Benzoquinones; D011622:Pterins; D001708:Biopterins; C004532:quinone; D014442:Monophenol Monooxygenase