9.B.423.1.1
Tyrosinase, Tyr or TYR, of 529 aas and 2 TMSs, one signal sequence at the N-terminus, and one very hydrophobic TMS at the C-terminus. It is a copper-containing oxidase that functions in the formation of pigments such as melanins and other polyphenolic compounds (Olivares and Solano 2009). This enzyme, for which the 3-d structure is known, catalyzes the initial and rate limiting step in the cascade of reactions leading to melanin production from tyrosine (Lai et al. 2018). In addition to hydroxylating tyrosine to DOPA (3,4-dihydroxyphenylalanine), TYR also catalyzes the oxidation of DOPA to DOPA-quinone, and possibly the oxidation of DHI (5,6-dihydroxyindole) to indole-5,6 quinone ((Hutchinson et al. 2019). It forms a trimeric complex with TYRP1 (TC# 9.B.423.1.2) and TYRP2 (TC# 9.B.423.1.3) (Lavinda et al. 2021).