FIG 6.

Virulence of phage-resistant mutants, relative to controls, in a tissue-culture model of S. flexneri pathogenicity. (A) Intracellular growth curves of wild-type M90T (purple), M90TΔompA (yellow), M90TΔmxiH (red), R1 (black circle), R2 (black square), R3 (black triangle), R4 (black inverted triangle), and R5 (black diamond) bacteria. Error bars show standard deviations of the mean of three technical replicates. (B through I) Plaque assays of wild-type M90T, M90TΔompA, M90TΔmxiH, R1, R2, R3, R4, and R5, respectively, on monolayers of Vero cells at MOI of 5 (bacteria CFU relative to Vero cells) after 72 h incubation. Data are representative of at least three separate experiments.