A storage polysaccharide, similar in structure to * starch, important in animals but not found in plants. It is however present in certain bacteria, blue-green algae, and fungi. It is a branched glucan, like amylopectin, but the branching is more frequent, occurring every 8-12 glucose residues. The enzyme that catalyses glycogen synthesis in bacteria is similar to starch synthetase in that it requires ADP-glucose as a substrate. Breakdown of glycogen, like starch breakdown, is catalysed by * amylase. |
