Alteration of phagocyte functional activity depending on the presence of pR50 plasmid in bacteria

: The relationship between the presence, or the absence, of conjugative plasmid pR50 detected in Klebsiella oxytoca 89, in the isogenic pairs of attenuated strains Shigella flexneri 2a 516 Near and Salmonella typhimurium 129 Rifr and the regeneration of the active forms of oxygen by mouse peritoneal phagocytizing cells was studied. As indicated by the data obtained in the course of the experiment, plasmids pR50 could influence the chemiluminescent response of phagocytes. The inhibition of the synthesis of oxygen metabolites was found to occur at the primary stage of the infectious process, that later this synthesis increased, that facilitated the survival of the animals infected with the cultures carrying plasmid pR50.