UDP-glucuronosyltransferase activities: Guidelines for consistent interim terminology and assay conditions

Glucuronide formation is a major pathway in the biotransformation and elimination of a wide variety of lipid-soluble endogenous compounds and xenobiotics. The reaction is catalysed by a family of closely related enzyme forms of UDP-glucuronosyltransferase(GT). This enzyme(s) has attracted many scientists because of a variety of interesting features, such as the phospholipid-dependence of its catalytic activity, latency of GT activity in the microsomal membrane and differential inducibility by hormones and xenobiotic inducers. In light of recent developments in enzyme isolation and purification and in immunochemical quantitation of the enzyme protein it was felt by most of the participants that an effort should now be made to describe a standardized terminology and assay procedure for GT. An ad hoc committee of the authors suggested the recommendations discussed later.