<cell biology> A copper containing protein (a monoxygenase) that catalyses the oxidation of tyrosine and sets in train spontaneous reactions that yield melanin, the black pigment of skin, hair and eyes. The first intermediate is 3, 4 dihydroxyphenylalanine (DOPA). Lack of tyrosinase activity is responsible for albinism.

This entry appears with permission from the Dictionary of Cell and Molecular Biology

(11 Mar 2008)