Glycogenin is an enzyme involved in converting glucose to glycogen. It acts as a primer, by polymerizing the first few glucose molecules, after which other enzymes take over. It is a homodimer of 37-kDa subunits and is classified as a glycosyltransferase.
It catalyzes the chemical reaction:
- UDP-alpha-D-glucose + glycogenin UDP + alpha-D-glucosylglycogenin
Thus, the two substrates of this enzyme are UDP-alpha-D-glucose and glycogenin, whereas its two products are UDP and alpha-D-glucosylglycogenin.
Read more about Glycogenin: Nomenclature, Discovery, Function, Structure, Isozymes