[Relationship between the electron structure of phosphates and the problem of ATP synthesis and utilization]

The nature of macroergic bonds and some problems of ATP formation and utilization are considered in terms of electron structure of phosphates. The main acting compound in the ATP synthesis and in the reactions of transfer and utilization of the energy of macroergic bonds as well, is ATP terminal phosphate or phosphoryl group which in the free state is a monomeric methaphosphate-ion. High reactive ability of monomeric methaphosphate-ion, its affinity of lown electrom pairs is conditioned by the presence of a vacant sp3-orbitals in phosphor atom of methaphosphate-ion. Therefore in the reactions with ATP participation the phosphoryl group plays the role of electrophilic agent. Formation of intermediate methaphosphate-ion preceding the synthesis of ATP from ADP during substrate phosphorylation results from the breakage of O--P bond, during which both electrons which form the bond stay in the oxygen atom. Another possible pathway of methaphosphate-ion formation is the ejaction of the electron from ortophosphate dianion with the help of suitable acceptor of the electrons, by light-stimulated pigment system of chloroplasts or chromatophores or singlet oxygen liberated during the decomposition of hydrogen peroxide with catalase. Due to the redistribution of electron density in the phosphate radical the latter turns into the monomeric methaphosphate-ion bound to ADP with the formation of ATP.