Contribution of P. aeruginosa mutS and dinB functionality to spontaneous RifR.

aRelevant phenotypes with respect to dinB and mutS function are indicated: +, wild-type; −, loss-of-function.bMedian mutation frequency is shown. Calculated frequencies are based on either 5 (for strain MPA32417 bearing plasmid pmutS) or 30 (for all other strains) independent determinations. Values in parentheses represent 95% confidence intervals, and were calculated as described [68].cFold-increase in median spontaneous mutation frequency relative to MPAO1, whose frequency was set equal to 1.0 (≡1.0).dPlasmid pmutS expresses the wild-type MutS protein (mutS+) from its native promoter.