Novel cofactors in copper-containing oxidases: Biogenesis and role in catalysis

Copper-containing oxidases are members of a growing family of enzymes which use protein-derived quinones and radicals as cofaov.rs. Galactose oxidase has a novel thioether cross link between C228 and Y272, the site of the radical. Studies on site-direct?0 variants reveal roles for the copper ligands in catalysis Copper is also in" r,ived in biogenesis of the thioether cross link and other post-translation' processing events Arnine oxidase from E coli has the quin"nu derived from trihydroxyphenylalanine (TPQ) as its c;.fsctor. Molecular events in the catalytic cycle are being characteris'.-d through crystallographic and biochemical studies The interplay between copper and TPQ in catalysis has similarities to the way copper >;.-irticipates in TPQ biogenesis.