EC 220.127.116.11 - Glycogen phosphorylase
IntEnz Enzyme Nomenclature
muscle phosphorylase a and b
- [(1right4)-alpha-D-glucosyl]n + phosphate = [(1right4)-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)-α-D-glucans. Some of these enzymes catalyse the first step in the degradation of large branched glycan polymers - the phosphorolytic cleavage of α-1,4-glucosidic bonds from the non-reducing ends of linear poly(1→4)-α-D-glucosyl chains within the polymers. The enzyme stops when it reaches the fourth residue away from an α-1,6 branching point, leaving a highly branched core known as a limit dextrin. The 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.
Links to other databases
A simple method for the preparation of crystalline potato phosphorylase and Q-enzyme.Nature 171 : 983-984 (1953). [PMID: 13063502]
Purification and properties of glycogen phosphorylase from Escherichia coli.Arch. Biochem. Biophys. 127 : 175-186 (1968). [PMID: 4878695]
Lobster muscle phosphorylase: purfication and properties.J. Biol. Chem. 234 : 3146-3153 (1959). [PMID: 13812491]
The structure, function and control of glycogen phosphorylase.In: Campbell, P.N. and Greville, G.D. (Eds.) Essays in Biochemistry, vol. 6 , Academic Press , London and New York , 1970 , 23-68
Crystalline muscle phosphorylase. I. Preparation, properties, and molecular weight.J. Biol. Chem. 151 : 21-29 (1943).
The breakdown and synthesis of starch by an enzyme from pea seeds.Proc. R. Soc. Lond. B Biol. Sci. 128 : 421-450 (1940).
[EC 18.104.22.168 created 1961, modified 2013]