phosphorylase kinase

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Related to phosphorylase kinase: Glycogen phosphorylase

phos·phor·y·lase ki·nase

an enzyme that uses ATP to phosphorylate phosphorylase b and thus reform phosphorylase a, the active form of phosphorylase; the active form of phosphorylase kinase is itself a phosphorylated protein; on dephosphorylation of phosphorylase kinase, the enzyme is inactivated; it can be rephosphorylated with a cAMP-dependent protein kinase; phosphorylase kinase is deficient in certain types of glycogen storage disease.

phosphorylase kinase

/phos·phor·y·lase ki·nase/ (fos-for´ĭ-lās ki´nās) phosphorylase b kinase; an enzyme that catalyzes the phosphorylation and activation of glycogen phosphorylase, a step in the cascade of reactions regulating glycogenolysis.


a key regulatory enzyme that, in the presence of inorganic phosphate, catalyzes the removal of one glucose unit from glycogen to glucose-1-phosphate.

citrulline phosphorylase
see ornithine carbamoyl transferase.
phosphorylase kinase
an enzyme that activates phosphorylase by catalyzing the phosphorylation of serine. See also kinase.