title: Escherichia coli merodiploids with altered ratios of episomal to chromosomal RNA polymerase activity.
abstract: Starting with an E. coli merodiploid strain (rpoB+ (rifS)/rpoB- (rifR)) containing equal amounts of rifampicin-sensitive and resistant RNA polymerase activities, mutants were isolated that had a disproportionately high ratio of the rifampicin-resistant enzyme activity. With one strain it is shown that the mutation responsible for this phenotype is closely linked to the rifR (rpoB-) allele.
mesh_terms: D002876:Chromosomes, Bacterial; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism*; D004171:Diploidy; D004926:Escherichia coli / Q000235:genetics*; D005838:Genotype; D007700:Kinetics; D009876:Operon; D010641:Phenotype; D012293:Rifampin / Q000494:pharmacology; D014161:Transduction, Genetic
chemical_list: D012321:DNA-Directed RNA Polymerases; D012293:Rifampin