title: Spontaneous deletions of drug-resistance determinants from Salmonella typhimurium in Escherichia coli.
abstract: Plasmids isolated from two different clinical isolates of Salmonella typhimurium, both resistant to the antibiotics ampicillin, tetracycline, streptomycin and chloramphenicol, were used to transform Escherichia coli. Segregation of antibiotic-resistance determinants occurred in both cases. Analysis of plasmids from one set of segregants by DNA-DNA hybridisation indicated that the segregation was due to precise deletions in the transforming plasmid.
mesh_terms: D000667:Ampicillin / Q000494:pharmacology; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002701:Chloramphenicol / Q000494:pharmacology; D002872:Chromosome Deletion; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics*; D010641:Phenotype; D011815:R Factors; D012486:Salmonella typhimurium / Q000187:drug effects / Q000235:genetics*; D013307:Streptomycin / Q000494:pharmacology; D013752:Tetracycline / Q000494:pharmacology; D014169:Transformation, Bacterial
chemical_list: D000900:Anti-Bacterial Agents; D002701:Chloramphenicol; D000667:Ampicillin; D013752:Tetracycline; D013307:Streptomycin