Inhibition of lysyl oxidase by disulfhydryls, diamines and sulfhydryl-amines.

Lysyl oxidase is the enzyme responsible for the oxidative deamination of lysine and hydroxylysine residues in collagen and elastin. Lysyl oxidase activity is irreversibly inhibited by disulfhydryls and diamines while the sulfhydryl-amine, penicillamine, inhibits reversibly. Monosulfhydryls or monoamines do not inhibit significantly. All inhibitors tested react directly with the enzyme. The disulfhydryls do not inhibit through thiolytic cleavage as an equivalent amount of β-mercaptoethanol does not produce significant inhibition (1). The possibility of adduct formation between these bifunctional inhibitors and aldehyde or pyridoxine derived cofactors within the enzyme is discussed.