Protocollagen Proline Hydroxylase Activity in the Skin of Normal Human Subjects and of Patients with Scleroderma

Abstract

The activity of parotocollagen proline hydroxylase was assayed in punch biopsy specimens of human skin. The enzyme in human skin was similar to that from animal sources, in that it was recovered in the soluble protein fraction and in that it required atmospheric oxygen, ascorbate, α-ketoglutarate and ferrous iron. The activity of protocollagen proline hydroxylase was highest in foetuses and newborn infants, and decreased with advancing age. A slight elevation of the enzyme activity was found in three out of five patients with actively progressing scleroderma.