FIG 6.

The roles of bacterial motility and morphology in macrophage phagocytosis of the ΔspxA1 mutant. (A) Gentamicin protection assay measuring intracellular bacteria at 1 h postinfection of iBMMs. (B) Gentamicin protection assay after bacteria were centrifuged onto the host cells immediately after infection. The means and SEM of three biological replicates are shown for panels A and B. P values were calculated using an unpaired Student t test compared to wt cells. *, P < 0.05; n.s., P > 0.05. (C) iBMMs were infected with centrifugation for 15 min and stained to enable differentiation of extracellular (E) and intracellular (I) bacteria. The perimeters of cells in each compartment were measured using Celltool. Cell perimeters were measured from two biological replicates where at least 1,000 bacteria or 10 fields of view were quantified. The lines represent the means. Distributions were compared using Kolmogorov-Smirnov tests. *, P < 0.05.