Nucleotide activation of liver microsomal glucuronidation.

The classical studies of Dutton and Storey (1) have shown that liver microsomes catalyze the transfer of glucuronic acid from uridine diphosphate glucuronic acid to phenols. In an attempt to detect a reaction between uridine diphosphate glucuronic acid and uridine diphosphate N-acetylglucosamine, the effect of the latter on phenol glucuronidation was tested. It was expected that a reaction between the two nucleotides should decrease glucuronidation. Contrary to the expectation, increased formation of phenyl glucuronide was obtained on adding uridine diphosphate N-acetylglucosamine. The largest effect was produced with rat liver microsomes and was further increased by addition of adenosine triphosphate. Inasmuch as sugar nucleotides such as uridine diphosphate glucose or guanine diphosphate mannose could not replace uridine diphosphate N-acetylglucosamine, it was considered of interest to study the phenomenon in more detail.