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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.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(fɒsˈfɒrɪˌleɪs; -ˌleɪz)
(Biochemistry) any of a group of enzymes that catalyse the hydrolysis of glycogen to glucose-1-phosphate
[C20: from phosphorus + -yl + -ase]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(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.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
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.