engleski

Maximum entropy production principle (MEPP) in generalized Michaelis-Menten kinetics

MEPP is a physical principle, widely used for quantitative explanation of non equilibrium phenomena in physics, chemistry and biology [1-3]. Here, we applied MEPP to study two and three state reversible Michaelis-Menten kinetic schemes of enzymatic reactions. By applying constraints as a diffusional limit for kinetic constants, constant free energy differences between enzymatic states and constant thermodynamic force, we calculated Shannon information entropy and entropy production of the entire reaction system as a function of forward rate constants. We found maxima in the net steady-state metabolic flux, total entropy production and Shannon entropy for equal values of forward rate constants. Moreover, for these values an analytical expression derived gives a relation between substrate and product concentrations at which enzymes operate in the optimal way. In conclusion, we demonstrated that MEPP is an appropriate selection principle for evolutionary optimization of enzymes. [1]Martyushev, L.M., Seleznev V.D. (2006) Physics Reports 426: 1-45. [2]Juretic, D., Zupanovic, P. (2003) CBC 27: 541 - 553. [3]Dewar, R.C., Juretic, D., Zupanovic, P. (2006) Chem. Phys. Lett. 430: 177-182.

entropy production; enzymatic reaction

DOI 10.1007/s00249-009-0478-1