Glucuronosyltransferase, UDP-: A liver enzyme essential to the disposal of bilirubin (the chemical that results from the normal breakdown of hemoglobin from red blood cells). The enzyme is responsible for what is called the glucuronidation reaction. UDP acts as a catalyst for the transfer of the glucuronic acid component of UDP-glucuronic acid to a substrate molecule. The resulting glucuronide is more easily eliminated from the body by the kidneys into the urine.
See: Deficiency, UDP-glucuronosyltransferase, Gilbert's Disease.