FIG 6.

In vitro growth phenotypes of transposon mutants and complemented strains. The growth of mutants and complemented strains was assessed by the IFU propagation ratio. McCoy cells were infected with each strain in 24-well plates. At 20 to 22 hpi, images were taken for inclusion counting by fluorescence microscopy. At 26 hpi, the cells were lysed and the bacteria were inoculated onto fresh McCoy cells for IFU determination. The data are expressed as means, and the error bars indicate standard deviations. Statistical comparisons between the transposon mutants, complemented strains, and IGR::Tn control were analyzed using one-way ANOVA with Dunnett’s test for multiple comparisons. *, P < 0.05; **, P < 0.01.