The debranching process in glycogen catabolism

a. A glycogen chain following activity by phosphorylase, which cleaves off glucose residues to within four residues of the branch point.

b. The glycogen chain following transferase activity by the debranching enzyme. The three remaining glucose residues with linkage have been transferred to a nearby nonreducing end.

c. The glycogen chain following a(16)-glucosidase activity by the debranching enzyme, which has removed the last remaining glucose residue of the branch.

Phosphorylase will cleave off all but four glucose units of the newly elongated branch, beginning the debranching process again.