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Related to Phosphorylase a: Phosphorylase b, Phosphorylase kinase


 (fŏs′fər-ə-lās′, -lāz′)
Any of a class of enzymes that catalyze the attachment of a phosphate group to another molecule.


(fɒsˈfɒrɪˌleɪs; -ˌleɪz)
(Biochemistry) any of a group of enzymes that catalyse the hydrolysis of glycogen to glucose-1-phosphate
[C20: from phosphorus + -yl + -ase]


(ˈfɒs fər əˌleɪs, -ˌleɪz, fɒsˈfɔr ə-, -ˈfɒr-)

any enzyme, occurring widely in animal and plant tissue, that in the presence of an inorganic phosphate catalyzes the conversion of glycogen into sugar phosphate.
References in periodicals archive ?
First, 0.4 ml of the enzyme was incubated with 2.0 mg of glycogen for 20 min at 35 [degrees]C, then the reaction was initiated by the addition of 0.2 ml of 0.016 M glucose-1-phosphate (G-1-P) to one tube (phosphorylase a) and a mixture of 0.2 ml of G-1-P and 0.004 M adenosine-5-monophosphate (phosphorylase ab) to another tube.
The percentage of glycogen phosphorylase a declined from a maximum of 100% in quiescent gemmules to a minimum of 84% at 42 h.
10 NATURE, Hajdu and his team photographed the patterns produced by a crystal of the enzyme phosphorylase as it was bathed with maltoheptase, a molecule that binds with the protein enzyme.