title: Melanogenesis inhibition due to NADH.
abstract: The effect of NADH on melanogenesis under aerobic conditions involves three types of reaction: (a) acting as tyrosinase substrate (a competitive substrate of L-tyrosine and L-DOPA), (b) irreversible inactivation acting as a suicide substrate of tyrosinase, and (c) non-enzymatic reduction of o-dopaquinone by NADH. Under anaerobic conditions, NADH irreversibly inhibits the enzymatic forms met-tyrosinase and deoxy-tyrosinase. In this paper, we kinetically characterize this coenzyme as it acts as a tyrosinase suicide substrate and propose a kinetic mechanism to explain its oxidation by tyrosinase. In addition, the compound is characterized as an irreversible inhibitor of met-tyrosinase and deoxy-tyrosinase.
authors.affiliation: GENZ: Investigative Group for Enzymology, 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: Mary
authors.initials: M
authors.lastname: Garcia-Molina
authors.forename: Peter Anthony
authors.initials: PA
authors.lastname: Garcia-Ruiz
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: D000363:Agaricales / Q000737:chemistry / Q000502:physiology; D016227:Benzoquinones; D004295:Dihydroxyphenylalanine / Q000031:analogs & derivatives; D005656:Fungal Proteins; D007211:Indoles / Q000037:antagonists & inhibitors* / Q000378:metabolism; D007700:Kinetics; D008543:Melanins / Q000378:metabolism; D014442:Monophenol Monooxygenase / Q000737:chemistry / Q000378:metabolism*; D009243:NAD / Q000494:pharmacology*; D010084:Oxidation-Reduction; D013379:Substrate Specificity
chemical_list: D016227:Benzoquinones; D005656:Fungal Proteins; D007211:Indoles; D008543:Melanins; C009904:melanogen; D009243:NAD; D004295:Dihydroxyphenylalanine; C035157:dopaquinone; D014442:Monophenol Monooxygenase