<enzyme, molecular biology> Widely used abbreviation for phosphokinase, an enzyme catalysing transfer of phosphate from ATP to a second substrate usually specified in less abbreviated name, for example creatine phosphokinase (creatine kinase), protein kinase. Serine / threonine kinases phosphorylate on serine or threonine residues, tyrosine kinases on tyrosines.
(18 Nov 1997)