Gamma-radiolysis of aqueous solution of histidine.

The dependence of Gi(-M) values of histidine on the concentration of irradiated 10(-4) - 10(-1)M solutions, pH and the presence of O2, N2O and sec-butyl alcohol was investigated. In oxygen-free medium the maximum radiation sensitivity of histidine was found at pH 5--8; in oxygenated solutions it was shifted to the 6--1 pH range. The formation of radiation products was also studied. The course of radiation decomposition of histidine depends on the presence of oxygen and on the pH of irradiated solution.