phosphorylase-A

Function

• glycogen phosphorylase (active form)
• phosphorylation of Ser-15 converts phosphorylase B (unphosphorylated) to phosphorylase A

(1,4-alpha-D-glucosyl)(n) + phosphate
                   <-->
(1,4-alpha-D-glucosyl)(n-1) + alpha-D-glucose 1-phosphate

Cofactor: pyridoxal phosphate

Structure

• dimers associate into a tetramer to form the enzymatically active phosphorylase A
• belongs to the glycogen phosphorylase family

More general terms

• glycogen phosphorylase