[Effect of ozone on bacteriophages in the phage--host-cell system]

The antiviral action of ozone was studied using Escherichia coli K-12 AB1157 virulent phage T4 and Pseudomonas aeruginosa PAO1 temperate phage SM as models depending on the phage state during the action: a free phage, a phage in the presence of sensitive host cells, or a vegetative phage. Bacteriophages T4 and SM were found to be much more sensitive to ozone as compared to the bacterial strains AB1157 and PAO1. The latter protected phage particles against the activation by ozone at a concentration which effectively inactivated these phages in the absence of the bacteria. Ozone also exerted an inhibiting effect on vegetative phage SM, and the degree of inhibition decreased with the termination of intracellular growth stages.