FIG 6.

metJ deletion suppresses pyroptosis and invasion independently of the flagellar regulon. (A) Reductions in pyroptosis and invasion in the ΔmetJ mutant do not depend on fliZ. (B) Reductions in pyroptosis and invasion in the ΔmetJ mutant do not depend on flhDC. Because flhDC mutants are immotile, cells were infected and centrifuged at 500 × g for 10 min in order to promote host-bacterium interactions. For the assays whose results are presented in panels A and B, pyroptosis and invasion in 18592 LCLs were measured at 3 h postinfection using a modified gentamicin protection assay across at least three independent experiments. Percent cell death represents all 7-AAD⁺ cells under each infected condition, with the baseline uninfected cell death being subtracted. See the gating in Fig. 1A. (C) Reductions in motility in the ΔmetJ mutant do not depend on hilD. Motility was measured after 6 h at 37°C on 0.3% LB agar. Data for panel C come from three biological replicates across two experiments. For panels A, B, and C, data were normalized to the global mean, and P values, indicated at the top, were calculated through a one-way analysis of variance with Sidak's multiple-comparison test.