A Thermodynamic Model for ATP Synthesis

Different systems of coupling for ATP synthesis namely localized and delocalized coupling are considered. Based on the principles of nonequilibrium thermodynamics and the studies performed in this regard, we have proved that the delocalized coupling of ATP leads to the minimum rate of entropy production in the steady state conditions. This has shown a good agreement with the experimental results available in the field of thermodynamics of ATP Synthesis. The efficiency of the process for ATP synthesis is studied, showing the existence of some limitations in the maximum obtainable efficiency. Furthermore, the relationship between the dissipation of free energy and the efficiency of ATP synthesis process in living cells is discussed, revealing that it is favorable to have the minimum dissipation of free energy together with the maximum efficiency. To satisfy this favor, the system operates as close to equilibrium as possible and the kinetic and energetic factors are wisely selected. In the end, the dissipation of free energy in biological systems is shown to be dependent on the distance from the equilibrium as well as the physical system of coupling.

کلیدواژه ها:

ATP synthesis ، Proton transportation ، Oxidative phosphorylation ، Localized coupling ، Delocalized coupling