T6SS competitive killing assays to measure the effect of replacing the Tse15 clade cleavage motif or the toxin cleavage motif with an in-frame FRT site on the ability of A. baumannii to kill vulnerable E. coli prey in a Tse15-dependent manner. Predator strains used were AB307_0294 wild-type, a Δ tssM mutant (inactive T6SS), a Δ tse15 mutant, a tse15 clade cleavage mutant ( tse 15CC::FRT) and a tse15 toxin cleavage mutant ( tse 15TC::FRT). Bars represent mean of four biological replicates, error bars represent SEM. Statistical significance was determined using ANOVA with Tukey’s multiple comparisons test. **** p < 0.0001.
