EC number 2.4.1.1 IntEnz IntEnz view ExPASy NiceZyme view | CAS number 9035-74-9 BRENDA BRENDA entry KEGG KEGG entry | |
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Phosphorylases are enzymes that catalyze the addition of a phosphate group from an inorganic phosphate (phosphate+hydrogen) to an acceptor.
Contents
A-B + PThey include allosteric enzymes that catalyze the production of glucose-1-phosphate from a glucan such as glycogen, starch or maltodextrin. Phosphorylase is also a common name used for glycogen phosphorylase in honor of Earl W. Sutherland Jr. who in the late 1930s discovered the first phosphorylase.
Function
Phosphorylases should not be confused with phosphatases, which remove phosphate groups. In more general terms, phosphorylases are enzymes that catalyze the addition of a phosphate group from an inorganic phosphate (phosphate + hydrogen) to an acceptor, not to be confused with a phosphatase (a hydrolase) or a kinase (a phosphotransferase). A phosphatase removes a phosphonate group from a donor using water, whereas a kinase transfers a phosphonate group from a donor (usually ATP) to an acceptor.
Types
The phosphorylases fall into the following categories:
All known phosphorylases share catalytic and structural properties [1].
Activation
Phosphorylase a is the active form of glycogen phosphorylase that is derived from the phosphorylation of the inactive form, phosphorylase b.
Pathology
Some disorders are related to phosphorylases: