Previous studies by Mudd, et al., have also been made on the reaction of ozone and amino acids. However, these investigations were carried out using a continuous flow of ozone which makes it difficult to obtain accurate kinetic data. Our results differ from those of Mudd, et al., both in the order of susceptibility of the amino acids in aqueous solution to oxidation by ozone and also in time scale (minutes as against seconds, as in the present study). From the present study, the following conclusions can be drawn. Ozone reacts extremely rapidly (less than one second) with those amino acids containing sulfur groups. The S-S linkage in single amino acids reacts with ozone on a time scale similar to that of the virus, while C-S-H and C-S-C groupings are attacked even quicker. However, the interaction of ozone with the enzyme is apparently with the S-S link and not the methionine group. Further, the isolated methionine acid reacts differently from the acid in a peptide chain with ozone. Apparently the effect of the entire peptide chain causes steric hindrance as well as physical-chemical changes in the micro-environment and hence slows down the kinetics.