Fig. 4.

NaxD is involved in resistance to cationic antimicrobials and alteration of bacterial surface charge.

A–C. Wild-type F. novicida (WT), the naxD deletion mutant (ΔnaxD) or the complemented strain (comp) were incubated with the indicated concentrations of (A) polymyxin B, (B) SDS or (C) Triton X-100 for 6 h. Cultures were then serially diluted and plated for cfu (n = 3 biological replicates).

D. The zeta potential of wild-type and ΔnaxD was measured (n = 10 technical replicates) and the results of three independent experiments were combined for statistical analysis.

In (A)–(C), bars represent the average and error bars represent the standard deviation of three biological replicates from one experiment. Data shown are representative of at least three independent experiments. Asterisks indicate significance as compared with wild-type. *P < 0.05, **P < 0.005, ***P < 0.0005.