title: Human, rabbit, bovine, and porcine creatine kinase isoenzymes are glycoproteins.
abstract: Human, rabbit, bovine, and porcine creatine kinase (CK) isoenzyme preparations were extensively purified by isoelectric focusing and high-performance liquid chromatography and tested for the presence of carbohydrate. In this study, all the CK isoenzymes demonstrated positive periodic acid-Schiff (PAS) reactions, indicating the presence of carbohydrate. It is concluded that CK is a glycoprotein as a carbohydrate, associated with the M subunit of human, rabbit, bovine, and porcine isoenzymes. Also, carbohydrate is an integral part of the B subunit of both rabbit brain and porcine heart CK. Loss of carbohydrate may be important in enzyme catabolism, yielding a pool of circulating modified CK protein that, to date, has remained undetected by traditional methods.
authors.affiliation: Department of Pathology, UCLA School of Medicine 90024-1732.
authors.forename: J H
authors.initials: JH
authors.lastname: McBride
authors.forename: D O
authors.initials: DO
authors.lastname: Rodgerson
authors.forename: L H
authors.initials: LH
authors.lastname: Hilborne
mesh_terms: D000818:Animals; D002417:Cattle; D003402:Creatine Kinase / Q000032:analysis*; D004591:Electrophoresis, Polyacrylamide Gel; D006023:Glycoproteins / Q000032:analysis*; D006801:Humans; D007527:Isoenzymes; D010503:Periodic Acid-Schiff Reaction; D011817:Rabbits; D013552:Swine
chemical_list: D006023:Glycoproteins; D007527:Isoenzymes; D003402:Creatine Kinase