Inhibition of prolyl hydroxylase by collagen

Abstract

Summary Heat-denatured collagens obtained from tissues of several vertebrate species strongly inhibited prolyl hydroxylase activity of both chick embryos and WI-38 fetal human lung fibroblasts. With 3,4- 3 H-L-proline-labeled “protocollagen” (“deoxycollagen” chains) as substrate and one of several kinds of unlabeled or tritium-labeled collagens as inhibitor, the inhibition of hydroxylase activity was shown to be non-competitive. If such inhibition were to occur in vivo, it could represent a significant mode of regulation of prolyl hydroxylase activity or a means by which the degree of hydroxylation of nascent collagen is controlled.