UDP-glucose is an intermediate in the synthesis of glycogen. and in galactose metabolism. It is made from UTP and glucose-1-phosphate by action of the enzyme UDP-glucose pyrophosphorylase.

UDP-glucose and UDG-galactose can be interconverted by the enzyme UDP-galactose-4-epimerase (Figure 13.14).

UDP-glucose can also be made in a reaction catalyzed by UDP-glucose pyrophosphorylase in which glucose-1-phosphate is linked to UTP to form UDP-glucose with splitting out of pyrophosphate (Figure 13.13).

UDP-glucose transfers glucose to dolichol phosphate to form dolichol phospho-glucose in synthesis of N-linked glycoproteins.

UDP-glucose is also an inhibitor of carbamoyl phosphate synthetase II, the primary regulatory enzyme in pyrimidine biosynthesis.