glycogen debranching enzyme activity

Definition

Target type: molecularfunction

Catalysis of the cleavage of branch points in branched glycogen polymers. [ISBN:0198506732]

Glycogen debranching enzyme activity is a crucial step in glycogenolysis, the breakdown of glycogen into glucose. This enzyme, also known as amylo-1,6-glucosidase, performs two distinct catalytic activities:

1. **Glucantransferase activity:** It transfers a trisaccharide unit (three glucose molecules) from a glycogen branch point (a 1,6-α-glucosidic linkage) to the non-reducing end of a nearby glycogen chain, effectively shortening the branch.

2. **α-1,6-glucosidase activity:** After the transfer reaction, it hydrolyzes the remaining single glucose molecule at the branch point, releasing it as free glucose.

These two activities work together to dismantle the highly branched structure of glycogen, exposing more glucose units for further breakdown by other enzymes like glycogen phosphorylase. This process ensures a steady supply of glucose for energy production, especially during periods of high energy demand.
'
"

Proteins (1)

Compounds (11)