Studies on Phenolic Steroids in Human Subjects: VI. Biosynthesis of Estriolglucosiduronic Acid-16-14C by Human Liver1

Abstract

Incubation of homogenates of human liver with uridinediphosphoglucosiduronic acid and estriol leads to the probable formation of estriol-16α-β-d-glucopyranosiduronic acid. The inclusion of uridinediphospho-N-acetylglucosamine in the incubation mixture increases the yield of conjugate. Competition experiments indicate that the 16α-transglucuronidase is probably a separate entity from the 3α-transferase. Optimal conditions for the reaction are investigated and a unit of enzyme activity is denned.