Glycogen breakdown

Step 1

Release of glucose-1-phoshate from glycogen

Step 1 Breakdown

gluco

Step 2

Isomerization of glucose-1-phosphate to glucose-6-phosphate

Step 2 breakdown

Enzyme used: phosphoglucomutase

Step 3

“Remodeling” of glycogen to facilitate further breakdown

Step 3 breakdown

Glycogen phosphorylase can only cleave alpha (1→4), it cant break the (1→6) bond.

• Uses the debranching enzyme so glycogen phosphorylase can continue

• Catalyzes 2 reactions:

  • Transferase activity that shift a block of three glucose residues from one branch to another

  • Alpha-1,6-glucosidase activity hydrolysis the bond to release a glucose