FIG 3.

Transformation frequencies of A. baumannii strains AB5075 (A) and AYE (B) of a 3.8-kbp-long PCR product carrying a mutation in the rpoB gene conferring resistance to rifampicin (final concentration of 50 ng/μl, 125 ng per sample). For both strains, either the wild type or their “T” (ΔAbaR/repaired comM) or ΔcomM derivatives were tested. At least seven independent transformation assays were performed on at least two separate occasions represented by separate dots and corresponding boxplots. All results were above the limit of detection (10⁻⁸). Pairwise comparisons using the nonparametric Mann-Whitney-Wilcoxon test (two-tailed) gave P values of at least <0.005 between transformation frequencies obtained for the wild-type/ΔcomM strains and the T derivatives.