Creatine phosphokinase kinase

Creatine phosphokinase activity has been reported to be minimally inhibited by hemolysis. Hemoglobin concentrations of 1.25 g/100 ml inhibit 5% and 2.5 g/100 ml, 12% (N5). However, in methods utilizing adenosine diphosphate in the reaction mixture, hemolysates containing 100 mg of hemoglobin per 100 ml may have apparent activities of 5-100 units/liter. The activity is presumably related to adenylate kinase in the erythrocyte (S33). In methods utilizing adenosine diphosphate in a coupled enzyme reaction with hexokinase and glucose-6-phosphatase, the inhibitory effect can be eliminated by adding sufficient adenosine mono-... 

Alteration of serum enzyme activity has been shown to be a sensitive parameter of tissue injury (20). While the activities of such enzymes as pyruvate kinase, lactate dehydrogenase, glutamate oxaloacetate transaminase, alkaline phosphatase, and creatine phosphokinase in rat serum were significantly altered by the deprivation of dietary vitamin E, the activities of these enzymes were not influenced by smoking exposure under the experimental conditions (Table I). 

Adenosine triphosphate creatine A-phosphotransferase (EC 2.7.3.2), also creatine phosphokinase. Creatine kinase is found in muscle and is responsible for the formation of creatine phosphate from creatine and adenosine triphosphate creatine phosphate is a higher energy source for muscle contraction. Creatine kinase is elevated in all forms of muscular dystrophy. Creatine kinase is dimer and is present as isozymes (CK-1, BB CK-2, MB CK-3, MM) and Ck-mt (mitochondrial). Creatine kinase is also used to measure cardiac muscle damage in myocardial infarction. See Bais, R. and Edwards, J.B., Creatine kinase, CRC Crit. Rev. Clin. Lab. ScL 16, 291-355, 1982 McLeish, M.J. and Kenyon, G.L., Relating structure to mechanism in creatine kinase, Crit. Rev. Biochem. Mol. Biol 40, 1-20, 2005. 

ATP phosphorylates creatine to form creatine phosphate in a reaction catalyzed by creatine kinase (also known as creatine phosphokinase). 

The sensitivity of this method is directly related to the apparent molar enthalpy of reaction, so that very endo- or exothermic reactions will be most readily followed. Examples of the application of this method to the determination of enzyme kinetic parameters include dihydrofolate reductase, creatine phosphokinase, hexo-kinase, urease, trypsin, HIV-1 protease, heparinase, and pyruvate carboxylase. 

Creatine kinase (also called creatine phosphokinase, or CPK) is a dimer of subunit molecular weight 40,000. The brain isozyme is a dimer of B subunits. In skeletal muscle, the principal form is a homodimer of M subunits. In cardiac muscle, 80-85% of the CK is MM, the balance is MB. These isozymes are electrophoretically distinct, as is mitochondrial CK. Depending on fiber type, 10-30% of CK activity is on the outer side of the inner mitochondrial membrane, 3—4% is at the M-lines, and the remainder is in... 

CREATINE KINASE (CREATINE PHOSPHOKINASE, CK, CPK) 103 Increases in serum levels... 

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