FIG 4.

Growth rate and colony variation scores of ruvA, ruvB, and recG mutants. (A) CFU/colony for the parent FA1090 recA6, ruvA::kan derivative, ruvB::ermC derivative, and recG::kan derivative grown without IPTG and in the presence of IPTG. Shown are results from a representative experiment, where the error bars represent the SEM for 3 to 5 colonies. Above the graph is the ratio of the CFU/colony of cells grown with IPTG (recA⁺) to that of cells grown without IPTG (recA) for each pair of samples. Shown are the averages from five experiments for the parent, ruvA::kan, and ruvB::ermC strains and from two experiments for the recG::kan strain, with parentheses representing the SEM. (B) Pilin-dependent colony morphology changes (PDCMC) of the parent FA1090 recA6 strain, ruvA::kan derivative, ruvB::ermC derivative, and recG::kan derivative grown in the presence of IPTG. Shown are the averages of results from 6 to 11 assays (of 10 colonies each), with error bars representing the SEM. Statistical significance was determined using Student's two-tailed t test. Asterisks indicate strains with P values of <0.05 relative to the parent strain for the time points 26, 28, and 30 h.