α-D-Glucose-1-phosphate is an intermediate in glycogen metabolism. It is a precursor in the biosynthesis of UDP-glucose, the glucose donor in glycogen biosynthesis. α-D-Glucose-1-phosphate can be formed during glycogen breakdown via phosphorolytic cleavage of glycogen by glycogen phosphorylase. It can be converted to glucose-6-phosphate by phosphoglucomutase. α-D-Glucose-1-phosphate is combined with CTP by α-D-glucose-1-phosphate cytidylyltransferase to form CDP-glucose in the first step of CDP-D-tyvelose biosynthesis in S. typhi. Bacterial sucrose phosphorylase converts sucrose and phosphate into D-fructose and α-D-glucose-1-phosphate.