Glycogen debranching enzyme and progressive muscle involvement, with variations caused by age of onset, rate of disease progression and severity. Patients with Type IIIb generally symptoms related to liver disease. Type III patients be distinguished by elevated liver enzymes, with normal uric acid and blood lactate levels, differing from other forms of GSD. In patients with muscle involvement, Type IIIa, the muscle weakness becomes predominant into adulthood and can lead to ventricular hypertrophy and distal muscle wasting. Glycogen debranching enzyme A debranching enzyme is a molecule that helps facilitate the breakdown of glycogen, which serves as a store of glucose in the body,
Glycogen phosphorylase glucose-6-phosphate by the enzyme phosphoglucomutase. Although the reaction is reversible in solution, within the cell the enzyme only works in the forward direction as shown below because the concentration of inorganic phosphate is much higher than that of glucose-1-phosphate. Glycogen phosphorylase can act only on linear chains of glycogen (α1-4 glycosidic linkage). Its work will immediately come to a halt four residues away from α1-6 branch (which are exceedingly common in glycogen). In these situations, a debranching enzyme is necessary, which will straighten out the chain in that area. In addition, the enzyme transferase shifts a block of 3 glucosyl