ATP is a main intermediate of chemical energy in the living organisms. It is mainly synthesized in H+-F1Fo- ATPases by utilizing energy equal to energy of foton either from oxidation of foods or from light via the process of oxidative- or photo-phosphorylation in energy transducing membranes of mitochondria, chloroplasts and bacteria. We propose a mechano-chemiosmotic model of electron transfer coupling ATP synthesis and cyclic low amplitude swelling-shrinkage. According to this model, an asymmetric contact between dimers of opposite bc1 complexes inside the intracristae space is formed during shrinkage of mitochondria, which is a mechanical regulator of electron transfer from [2Fe-2S] cluster to heme c1. In this model OH- is transferred into matrix and H+ slowly (about 8 msec) into intra-cristae during energization (a polarization of membrane , a reduction of cyt c1 and a shrinkage of intra-cristae space occur). The movement of protons to the matrix causes neutralization of hydroxyl ions, as a result of which energy is released. Such, the main energy is consumed for the synthesis of ATP, for delivery of phosphate ions in the hexamer with help C-terminal α-helix of γ-subunit as on a lift against the energy barrier, a formation of phosphoryl groups and the release of ATP molecules, synthesized from the hexamer.
coupling, ATP synthesis, electron transfer, swelling-shrinkage
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