FIG 6.

Random-peptides mixture (FK) hinder the evolution of resistance and cross-resistance toward it. (A) Data represent the concentration of AMPs where bacteria grew, normalized to initial MIC (n = 6; mean ± SEM; growth defined as an OD₅₉₅ of >0.3. Each graph shows the concentrations of AMPs through the evolution. FK, random peptide mixture. (B) Comparison of the relative AMP concentration after 29 transfers (n = 6; mean + SEM). *, P < 0.05; **, P < 0.01 (Mann-Whitney U test with Bonferroni correction). (C) Susceptibility of evolved strains toward FK20. (D) Susceptibility of FK evolved strains toward different AMPs. Data in panels C and D represent the mean of three independent experiments. Dashed lines indicate the MIC toward the AMP that it evolved with (not cross-resistance or sensitivity).