Elucidation of the tyrosinase/O₂/monophenol ternary intermediate that dictates the monooxygenation mechanism in melanin biosynthesis.

ABSTRACT: Melanins are highly conjugated biopolymer pigments that provide photoprotection in a wide array of organisms, from bacteria to humans. The rate-limiting step in melanin biosynthesis, which is the ortho-hydroxylation of the amino acid L-tyrosine to L-DOPA, is catalyzed by the ubiquitous enzyme tyrosinase (Ty). Ty contains a coupled binuclear copper active site that binds O₂ to form a μ:η²:η²-peroxide dicopper(II) intermediate (oxy-Ty), capable of performing the regioselective monooxygenation of para-substituted monophenols to catechols. The mechanism of this critical monooxygenation reaction remains poorly understood despite extensive efforts. In this study, we have employed a combination of spectroscopic, kinetic, and computational methods to

SUBMITTER: Kipouros I 

PROVIDER: S-EPMC9389030 | biostudies-literature | 2022 Aug

REPOSITORIES: biostudies-literature