Figure 4.

ErgA and ErgB are functionally unrelated to ExlBA. (A) β-Galactosidase activities of IHMA87 wild-type (WT) and ergAB mutant (ΔergAB) carrying exlBA::lacZ. Activities were measured after growth in LB at OD₆₀₀ = 1 and are represented as mean (in Miller Units) ± SD from three independent experiments. Statistical significance was assessed using two-tailed T-test. (B) Kinetics of bacterial cytotoxicity on A549 epithelial cells. Cells were infected at a MOI of 10 with the indicated strains in presence of propidium iodide (PI). PI incorporation is represented as mean ± s.e.m. from three independent experiments. (C) Survival curves of Galleria mellonella larvae infected with an average of 5 bacteria per larva. Forty larvae were used for each strain. Statistical testing was performed using log-rank test (P < 0.05).