Pyruvate kinase
Pyruvate kinase is a transferase enzyme that catalyzes the transfer of a phosphate group from phosphoenolpyruvate (PEP) to ADP, yielding one molecule of pyruvate and one molecule of ATP.
Contents
Chemical reaction
![PEP + ADP \rightleftharpoons Pyrvate + ATP](/wiki/images/math/6/a/e/6aefc45d5babff149006084e4e37f222.png)
Rate equation
The rate equation is represented by the allosteric regualation model of Monod, Wyman and Changeux (MWS). Fru1,6BP and Serine are activators and ATP is inhibiting. Simple Micahelis-Menten kinetics (Briggs Haldane) is used for ADP and reverse reaction [1]
![V_m \left( \left(\frac{\frac{[ADP]}{K_{ADP}}}{1+\frac{[ADP]}{K_{ADP}}}\right) \left( \frac{\frac{[PEP]}{Km_{PEP}}\left( 1+\frac{[PEP]}{Km_{PEP}} \right)^3 }{ \frac{L \left( 1 + \frac{[ATP]}{Ki_{ATP}} \right)^4 }{ \left( 1 + \frac{[SER]}{Ka_{SER}} \right)^4 \left( 1 + \frac{F1,6BP}{Ka_{F1,6BP}} \right)^4 } + \left( 1 + \frac{[PEP]}{Km_{PEP}} \right)^4} \right) - \left( \frac{\frac{[ATP][PYR]}{K_{ATP} \times K_{PYR} \times K_{eq}}}{1 +\frac{[ATP]}{K_{ATP}} + \frac{[PYR]}{K_{PYR}} + \frac{[ATP][PYR]}{K_{ATP} \times K_{PYR} }} \right) \right)](/wiki/images/math/8/e/c/8ec85891b22e0741e91b9e7f7885fe23.png)
Parameter values
Parameter | Value | Units | Organism | Remarks |
---|---|---|---|---|
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195[2] | ![]() |
HeLa cell line | |
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195172 | Recalculated from the ΔGº´ = - 31.4 KJ mol-1. | ||
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0.014 | mM | ||
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0.4 | mM | ||
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10 | mM | ||
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0.86 | mM | ||
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mM | ||
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2.5 | mM | ||
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1 | Dimensionless | ||
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5 | mM | For allosteric regulation the affinity constant is used. It is the inverted dissociation constant. so ![]() ![]() |
Alternative parameter values
References
- ↑ Monod J, Wyman J, Changeux J-P (1965). On the Nature of Allosteric Transitions: A Plausible Model . Journal of Molecular Biology 12:88–118 (doi)
- ↑ 2.0 2.1 2.2 2.3 Marín-Hernández A, Gallardo-Pérez JC, Rodríguez-Enríquez S et al (2011) Modeling cancer glycolysis. Biochim Biophys Acta 1807:755–767 (doi)
- ↑ 3.0 3.1 H.U. Bergmeyer. Methods of Enzymatic Analysis. Verlag Chemie, Winheim
- ↑ 4.0 4.1 Imamura K, Tanaka T (1982). Pyruvate kinase isoenzymes from rat, Methods Enzymol. 90 (1982) 150–165
- ↑ Arbitrary value
- ↑ Chaneton, B. et al.(2012) Serine is a natural ligand and allosteric activator of pyruvate kinase M2. Nature 491, 458–462