title: [Protective action of colicinogenic factor Ib-P9 on Escherichia coli cells defective in known repair functions after ultraviolet irradiation].
abstract: The presence of the plasmid colicinogenic factor Ib-P9 in Escherichia coli wild type cells is shown to increase bacterial survival after UV irradiation and the action of N-methyl-N'-nitro-N-nitrosoguanidine. The ability of the plasmid to cause the UV protection is observed in uvrA, uvrB, uvrC, polA, recB, recF E. coli strains, but the plasmid does not restore the UV resistance of the mutant cells to the wild type level. The protective effect of the plasmid CoI Ib-P9 depends on the recA+lexA+ genotype of the cells. The inhibition of protein synthesis (amino acid starvation) before and after UV irradiation does not prevent the UV protection by ColIb-P9. The nature of the plasmid-associated repair functions is discussed.
mesh_terms: D003086:Bacteriocin Plasmids; D004260:DNA Repair / Q000528:radiation effects*; D004269:DNA, Bacterial / Q000528:radiation effects*; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics / Q000528:radiation effects*; D008769:Methylnitronitrosoguanidine / Q000494:pharmacology; D009154:Mutation; D010957:Plasmids; D012486:Salmonella typhimurium / Q000235:genetics; D014170:Transformation, Genetic; D014466:Ultraviolet Rays
chemical_list: D004269:DNA, Bacterial; D008769:Methylnitronitrosoguanidine
vernacular_title: Zashchitnoe deĭstvie kolitsinogennogo faktora Ib-P9 na kletki Escherichia coli, defektnye po izvestnym reparativnym funktsiiam, posle ul'trafioletovogo oblucheniia.