This is a copper-containing oxidase that functions in the formation of pigments such as melanins and other polyphenolic compounds (Probable). Catalyzes the oxidation of o-diphenols such as dopamine (PubMed:26732497). Also oxidizes monophenols such as tyramine (PubMed:26732497). O2 + 2 tyramine = 2 dopamine 2 dopamine + O2 = 2 dopamine quinone + 2 H2O Binds 2 copper ions per subunit. Homodimer. Upon activation, a trypsin type protease cleaves prophenol oxidase to yield the active enzyme. Belongs to the tyrosinase family.