Potentiating Mechanism of Amino Acids on Inactivation of Phage J 1 by Ascorbic Acid

Abstract

The mechanism of the potentiating effect of amino acids on the inactivation of phage J 1 by ascorbic acid (AsA) was investigated using glycine, because the α-amino group and α-carboxyl group of amino acids were shown to be involved. Bubbling oxygen through the reaction mixture and the addition of hydrogen peroxide or transition metal ions to the reaction mixture enhanced the inactivation of phage by combination of AsA and glycine. In contrast, nitrogen bubbling and the addition of reducing agents, chelating agents or general radical scavengers inhibited the inactivation of phage. The results showed that oxygen radicals were involved in the inactivation reaction. Experiments with specific radical scavengers, superoxide dismutase or catalase showed that •OH was mainly responsible for the inactivating effect. Spectrophotometric studies showed that glycine increased the autoxidation rate of AsA. These results indicated that amino acids could enhance the inactivating effect of AsA by increasing the generation of •OH during autoxidation of AsA. In addition, induction of single-strand scission in phage DNA was shown by combination of AsA and amino acid in agarose gel electrophoresis.