prolyl hydroxylase


pro·lyl hy·drox·y·lase

an enzyme that catalyzes the hydroxylation of certain prolyl residues in collagen precursors using molecular oxygen, ferrous ion, ascorbic acid, and α-ketoglutarate; a vitamin C deficiency directly affects the activity of this enzyme; one form of this enzyme (prolyl 4-hydroxylase) synthesizes 4-hydroxyprolyl residues while another produces 3-hydroxyprolyl residues.