Lysyl oxidase differs from other copper amine oxidases in that its active quinone cofactor reflects cross-linking of a lysyl residue into the tyrosine-derived quinone nucleus found in the plasma and other copper amine oxidases. A model for the lysyl oxidase cofactor (LTQ), 3, 3- dimethyl-2, 3-dihydroindole-5, 6-quinone (4), was synthesized and found to be stable to both hydrolysis and oxidation events that prevent simpler models from functioning as turnover ...
