CATH Classification

Domain Context

CATH Clusters

Superfamily Glycogen Phosphorylase B;
Functional Family Alpha-1,4 glucan phosphorylase

Enzyme Information
Glycogen phosphorylase.
based on mapping to UniProt P00490
((1->4)-alpha-D-glucosyl)(n) + phosphate = ((1->4)-alpha-D-glucosyl)(n-1) + alpha-D-glucose 1-phosphate.
-!- This entry covers several enzymes from different sources that act in vivo on different forms of (1->4)-alpha-D-glucans. -!- Some of these enzymes catalyze the first step in the degradation of large branched glycan polymers - the phosphorolytic cleavage of alpha-1,4-glucosidic bonds from the non-reducing ends of linear poly(1->4)-alpha-D-glucosyl chains within the polymers. -!- The enzyme stops when it reaches the fourth residue away from an alpha-1,6 branching point, leaving a highly branched core known as a limit dextrin. -!- The description (accepted name) of the enzyme should be modified for each specific instance by substituting 'glycogen' with the name of the natural substrate, e.g. maltodextrin phosphorylase, starch phosphorylase, etc.

UniProtKB Entries (1)

Escherichia coli K-12
Maltodextrin phosphorylase

PDB Structure

External Links
Primary Citation
Phosphorylase Recognition and Phosphorolysis of its Oligosaccharide Substrate: Answers to a Long Outstanding Question
Watson, K.A., Mccleverty, C., Geremia, S., Cottaz, S., Driguez, H., Johnson, L.N.
Embo J.