ABSTRACT
Glycogen is a large polymer of glucose residues linked by α1–4 glycosidic bonds with branches every 10 residues or so via α1–6 glycosidic bonds. Glycogen provides an important energy reserve for the body. The two main storage sites are the liver and skeletal muscle where the glycogen is stored as granules in the cytosol. The granules contain not only glycogen but also the enzymes and regulatory proteins that are required for glycogen degradation and synthesis. Glycogen metabolism is important because it enables the blood glucose level to be maintained between meals and also provides an energy reserve for muscular activity. Glycogen degradation requires two enzymes; glycogen phosphorylase and glycogen-debranching enzyme. Three enzymes needed to synthesize glycogen are: UDP-glucose pyrophosphorylase; Glycogen synthase; and Branching enzyme.
