ENZYMATIC-SYNTHESIS OF URIDINE 5'-DIPHOSPHOGLUCURONIC ACID ON A GRAM SCALE

A practical route to uridine 5'-diphosphoglucuronic acid (UDP-GlcUA) from uridine 5'-diphosphoglucose (UDP-Glc) on a 1-g scale has been developed using uridine 5'-diphosphoglucose dehydrogenase (UDP-Glc DH, EC 1.1.1.22) from bovine liver. Crude UDP-Glc dehydrogenase was isolated from beef liver (450 units from 2.4 kg of frozen liver). Commercially available UDP-Glc dehydrogenase as well as a preparation from calf liver acetone powder were also evaluated as catalysts for large-scale production of UDP-GlcUA: both preparations exhibited too little activity to be synthetically useful. A platinum-catalyzed oxygen oxidation of UDP-Glc was also examined as a possible route to UDP-GlcUA: enzymatic oxidation was superior. These results establish a route to another of the important activated monosaccharides required for cell-free enzymatic syntheses of mammalian oligo- and polysaccharides.