Characterization of the pleiotropic phenotypes of rifampin-resistant rpoB mutants of Escherichia coli.

We used our collection of 17 sequenced rifampin resistance alleles in rpoB to perform a systematic analysis of the phenotypes historically reported with this class of mutants, including growth phenotype, ability to support the growth of different bacteriophages, ability to maintain the F' episome, interaction with mutant alleles at other loci, sensitivity to uracil, inhibition by 5-fluorouridine, and dominance. We found that mutational changes leading to the same phenotype were often located together and that certain phenotypes were associated with one another.