[Several physical aspects of intracellular energy transformation]

Physical principles underlying the chemiosmotic hypothesis of membrane phosphorylation are analysed. The utilization of free energy determined by dydrogen ions concentration difference across the membrane for ATP synthesis requires ATP-synthetase to be an entropy machine able to perform work on account of heat. The chemiosmotic hypothesis assumes the possibility of interchangeable utilization of both components of proton electrochemical potential-the membrane electrical difference and proton concentration gradient-for ATP synthesis. This assumption requires the fulfillment of practically unrealizable conditions. Energetic coupling of intracellular chemical reactions must be realized by means of a mechanism in which every act of energydonating reaction leads compulsory to one act of energyaccepting reaction. For such a mechanism both reactions ought to proceed essentially in one elementary act. For intracellular macromolecular and supramolecular systems it implies the necessity of excitation of specific mechanical slowly relaxing degrees of freedom.