Effects of tetrahydropterines on the generation of quinones catalyzed by tyrosinase.
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.
Garcia-Molina
Francis
F
Department of Biochemistry and Molecular Biology A, Faculty of Biology, University of Murcia, Murcia, Spain.
Munoz-Munoz
Joseph Louis
JL
Martinez-Ortiz
Francis
F
Tudela
Joseph
J
García-Cánovas
Francis
F
Rodriguez-Lopez
Joseph Neptune
JN
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*
D016227:Benzoquinones; D011622:Pterins; D001708:Biopterins; C004532:quinone; D014442:Monophenol Monooxygenase