Glycine and Histidine in Regulation of Free-Radical Dephosphorylation of Glycerol Phosphate in the Presence of Cu.sup.2+ Ions

The effect of Gly and His on homolytic fragmentation of glycerol phosphate with the cleavage of the phosphoester bond, induced by the Cu.sup.2+(Fe.sup.2+)-H.sub.2O.sub.2 redox systems or [gamma]-radiation, has been studied. It has been shown that under the conditions of Cu.sup.2+-mediated generation of HOË, Gly and His enhance the fragmentation at the amino acid : Cu.sup.2+ molar ratio between 1.6 : 1 and 3 : 1, whereas the increase in the molar ratio to [greater than or equal to]5 : 1 inhibit the fragmentation. The Cu(Gly).sub.2 complex in the presence of H.sub.2O.sub.2 has induces the glycerol phosphate decomposition, depending on the concentration. In the presence of Fe.sup.2+, Gly has not significantly affected the fragmentation, whereas His has accelerated the process by more than 2 times with the increase in its concentration in the system. In the case of the radiation-induced fragmentation, Gly has not affected the process, whereas His has acted as the inhibitor, depending on its concentration.