title: [Production of the mutant E strain of Rickettsia prowazekii by mutagen exposure].
abstract: The possibility of obtaining the mutants of R. prowazekii, strain E, by exposing these organisms to the action of N-methyl-N-nitro-N-nitrosoguanidine was studied; this substance, used in doses of 5-10 micrograms, showed a mutagenic effect on rickettsiae suspended in physiological saline, after their exposure for 10-20 minutes at 37 degrees C. The mutants thus obtained proved to be resistant to erythromycin and rifampicin and were characterized by heterogeneity in the degree and stability of their antibiotic resistance. The effectiveness of selection was increased if mutagen-treated rickettsiae were selected after the first passage in chick embryos. The induced mutants differed from the original rickettsial strain by their lower infectiosity for chick embryos.
mesh_terms: D000818:Animals; D002642:Chick Embryo; D004305:Dose-Response Relationship, Drug; D004352:Drug Resistance, Microbial; D004917:Erythromycin / Q000037:antagonists & inhibitors; D008769:Methylnitronitrosoguanidine / Q000494:pharmacology*; D009154:Mutation; D012283:Rickettsia prowazekii / Q000187:drug effects*; D012293:Rifampin / Q000037:antagonists & inhibitors; D013997:Time Factors
chemical_list: D008769:Methylnitronitrosoguanidine; D004917:Erythromycin; D012293:Rifampin
vernacular_title: Poluchenie mutantov shtamma E rikketsiĭ Provatseka pri mutagennom vozdeĭstvii.