Figure 2

(A) Relative quantification of ampC (ECL_00553) mRNA in the indicated strains, considering the wildtype ATCC 13047 strain basal level as 1 and using the rpoB gene for normalization. Horizontal columns represent the mean values from experimental replicates, whereas the error bars correspond to the SD (linear scale). White columns correspond to mRNA extracted in the basal situation whereas black ones correspond to induction conditions with cefoxitin (FOX) at the indicated concentrations (mg/l). (B) Virulence behavior of the indicated strains in the G. mellonella infection model. The proportion of surviving larvae after infection with 5E⁶ CFU/worm at the controlled time points (24, 48, 72, 96 h) is shown. Statistical analysis (Kaplan–Meier curves and log-rank test) was performed for pairwise comparisons between all strains. The two controls used in A were P. aeruginosa PA14 (high virulence) and K. pneumoniae 52K0 (low virulence). ***p value < 0.001; **p value < 0.01; *p value < 0.05; n.s. not significant, i.e., p value > 0.05.