Creatine kinase, kinetics

Ye, Y. Wang, C. Zhang, J. Cho, Y.K. Gong, G. Murakami, Y. Bache, R.J. Myocardial creatine kinase kinetics and isoform expression in hearts with severe LV hypertrophy. Am. J. Physiol., 281, H376-H386 (2001)... 

Spectral Analysis. - A new method of analysis of ATP utilisation and resynthesis has been developed which simulates cellular ATP flux, mitochondrial oxidative phosphorylation and creatine kinase kinetics. The model was used to examine previously published P NMR data of changes in PCr and Pi in resting muscle, muscle exercising during ischaemia and muscle in aerobic recovery. The model allowed estimation of the maximal velocity of oxidative... 

Some Kinetic Parameters for Analogs of Creatine in the Creatine Kinase Reaction (71)... 

Grossman, S.H., Pyle, J., and Steiner, R.J. (1981) Kinetic evidence for active monomers during the reassembly of denatured creatine kinase. Biochemistry 21, 6122. 

This muscle phosphotransferase (EC 2.132) catalyzes the reversible rephosphorylation of ADP to form ATP (/.c., T eq = [ATP][Creatine]/([Creatine phosphate] [ADP]) = 30). In resting muscle, creatine phosphate is synthesized at the expense of abundant stores of ATP intracellular creatine phosphate stores often reach 50-60 mM. If ATP is suddenly depleted by muscle contraction, its product ADP is immediately converted back into ATP by the reverse of the creatine kinase reaction. Depending on the pH at which the enzyme is studied, the kinetic reaction can be either rapid equilibrium random or rapid equilibrium ordered. A-Ethylglycocyamine can also act as a substrate. 

Creatine kinase-MgADP-creatine abortive, ABORTIVE COMPLEXES CRiTiCAL CONCENTRATiON ACTIN ASSEMBLY KINETICS END-WISE DEPOLYMERIZATION MICROTUBULE ASSEMBLY KINETICS Critical energy,... 

M. Schar, A.-M. M. El-Sharkawy, R. G. Weiss and P. A. Bottomley, Triple repetition time saturation transfer (TRiST) P spectroscopy for measuring human creatine kinase reaction kinetics. Magn. Reson. Med., 2010, 63,1493-1501. 

Hall, N. Addis, P. DeLuca, M. Mitochondrial creatine kinase. Physical and kinetic properties of the purified enzyme from beef heart. Biochemistry, 18, 1745-1751 (1979)... 

Yang, Y. Zhou, H.-M. Reactivation kinetics of 5,5 -dithiobis-(2-nitroben-zoic acid)-modified creatine kinase reactivated by dithiothreitol. Biochim. Biophys. Acta, 1388, 190-198 (1998)... 

Schlattner, U. Eder, M. Bolder, M. Khuchua, Z.A. Strauss, A.W. Walli-mann, T. Divergent enzyme kinetics and structural properties of the two human mitochondrial creatine kinase isoenzymes. Biol. Chem., 381, 1063-1070 (2000)... 

Kinetic studies on ADP-creatine kinase show the rate constants for association and dissociation of M-S and enzyme are practically independent of the nature of the metal, implying that the metal is not bridging and that this is a type I kinase.276... 

A commercial serum creatine kinase assay8 employs the kinetic method for enzyme quantitation. This three-enzyme, coupled assay involves the following sequence of reactions ... 

Fig. 5. Proposed structure of the abortive quaternary nitrate complex of creatine kinase (55) which may mimic the transition state of the enzymatic reaction, based on kinetic (54), EPR (55) and nuclear relaxation studies (88)...

Measure enzyme kinetics - saturation transfer for creatine kinase reaction Rb K congener. Measure K fluxes... 

CK catalyzes the reversible phosphorylation of creatine in the presence of ATP and magnesium. When creatine phosphate is the substrate, the resulting creatine can be measured as the ninhydrin fluorescent compound, as in the continuous flow Auto Analyzer method. Kinetic methods based on coupled enzymatic reactions are also popular. Tanzer and Gilvarg (40) developed a kinetic method using the two exogenous enzymes pyruvate kinase and lactate dehydrogenase to measure the CK rate by following the oxidation of NADH. In this procedure the main reaction is run in a less favorable direction. 

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. 

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