Purification and partial characterization of the enzyme for the hydroxylation of proline in protocollagen

摘要: A 200-fold purification was obtained for the enzyme which hydroxylates proline residues in protocollagen, polypeptide precursor of collagen. Essentially all enzymic activity recovered soluble protein fraction chick embryo homogenates. Ferrous iron, ascorbate, and α-ketoglutarate were cofactors reaction with purified enzyme. The did not hydroxylate free proline, it either tripeptide, glycyl-l-prolyl-l-proline, or poly-l-proline II a molecular weight about 15,000. synthetic polytripeptide, (14C-l-prolylglycyl-l-prolyl)n, 4000 hydroxylated, results indicated that is specific second position after glycine, hydroxyproline collagen found. 30-fold preparation also hydroxylated lysine cofactor requirements similar to those hydroxylation proline-labeled protocollagen. question whether single performs both hydroxylations resolved, but general characteristics enzymes suggest might be appropriate call them protocollagen hydroxylases.