FIG 6.

Effect of mutS on ruvB recG synthetic lethality. Viability of strains grown in the presence of IPTG. Shown are the ruvB recG (blue), ruvB recG ΔmutS (green), and ruvB recG mutS-F32A (red) strains and the single ruvB mutant (turquoise). The cells were grown on plates for 22 h in the absence (solid bars) and presence (striped bars) of IPTG, with the number or CFU per colony measured for 3 to 4 colonies each. The assay was performed 6 times, except for the assay for the single ruvB mutant, which was done 4 times. Error bars represent the SEM, and the asterisk denotes a Student's two-tailed t test value of P < 0.05 compared to the ruvB recG strain grown with IPTG.