title: [Effect of conjugative R plasmids on the virulence of antibiotic-sensitive Salmonella strains and their streptomycin-resistant mutants].
abstract: The pathogenicity level of antibiotic sensitive and streptomycin resistant strains of S. typhimurium, S. paratyphi B and S. kottbus changed under the effect of identical R plasmids more frequently in contrary directions. The conjugative plasmids of antibiotic resistance widened the ranges of the virulence changes in the Salmonella serovars for albino mice. It was found that 7 out of 8 plasmids studied significantly decreased and increased the virulence of the antibiotic sensitive Salmonella strains. As a rule, R plasmids of various origin decreased the virulence of all the tested streptomycin chromosome resistant causative agents of salmonellosis.
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D003227:Conjugation, Genetic / Q000187:drug effects*; D004352:Drug Resistance, Microbial; D051379:Mice; D009154:Mutation; D011815:R Factors / Q000187:drug effects*; D012475:Salmonella / Q000187:drug effects / Q000235:genetics* / Q000472:pathogenicity; D012484:Salmonella paratyphi B / Q000187:drug effects / Q000235:genetics / Q000472:pathogenicity; D012486:Salmonella typhimurium / Q000187:drug effects / Q000235:genetics / Q000472:pathogenicity; D013307:Streptomycin / Q000037:antagonists & inhibitors*; D014774:Virulence / Q000187:drug effects
chemical_list: D000900:Anti-Bacterial Agents; D013307:Streptomycin
vernacular_title: Vliianie kon"iugativnykh R-plazmid na virulentnost' chuvstvitel'nykh k antibiotikam shatmmov sal'monell i ikh streptomitsinorezistentnykh mutantov.