Human tyrosinase (TYR)

Human tyrosinase is a copper-containing enzyme encoded by the TYR gene, primarily expressed in skin melanocytes and localized in melanosomes[1][5]. It catalyzes the first two steps of melanin biosynthesis: the hydroxylation of L-tyrosine to L-DOPA and the subsequent oxidation of L-DOPA to dopaquinone[5]. This enzymatic activity is crucial for the production of melanin, the pigment that determines the color of human skin, hair, and eyes[4][5]. The protein is a membrane-bound glycoprotein, with a single transmembrane domain and an active site containing a binuclear copper center coordinated by conserved histidine residues[1][3][5]. Mutations or functional deficiency of tyrosinase are linked to oculocutaneous albinism type 1 and other pigmentary disorders[1][4]. Tyrosinase is a pharmacological target for treating hyperpigmentation, and various inhibitors have been developed for therapeutic and cosmetic uses, aiming to decrease melanin production[5].

Other names

tyrosinaseMonophenol monooxygenaseTYRtyrosinase enzyme

Inhibition of tyrosinase activity to reduce melanin synthesis Competitive inhibition at the active site (often binding to copper or other metal centers) Substrate analog inhibition (blocking substrate access) Metal chelation (removing copper ions crucial for activity)