Enzyme Inactivation by Chlorine Preparations. I. Inactivation of Alcohol Dehydrogenase, Urease, and Trypsin

In order to evaluate the chlorinating effectiveness, inactivation of crystalline enzyme preparations was measured at various concentrations of hypochlorite, hypochlorite-isocyanuric acid mixture, and chloramine. Urease inactivation occurred at the same rate by the three different chlorine preparations. Trypsin was inactivated similarly by hypochlorite and hypochlorite-isocyanuric acid mixture, but not by chloramine. In the case of alcohol dehydrogenase, chloramine reacted more effectively than hypochlorite, and hypochlorite-isocyanuric acid mixture was more effective than the other two. In the present work, added chlorine was consumed entirely by the enzyme solution within 1 min. Therefore it is apparent that the difference in the degree of enzyme inactivation among these chlorine preparations cannot be due merely to the difference in the amount of chlorine actually reacting with each enzyme. This fact implies that the mode of reaction between chlorine and the active site of each enzyme differs among these chlorine preparations.