FIG 1.

Impaired ACT activity reduces B. pertussis pathology in mice. (A) Bacterial lung colonization levels on day 3 after a low-dose infection (1 × 10⁷ CFU/mouse) with B. pertussis (Bp) expressing catalytically inactive ACT (TohamaI/mutAC [labeled mutAC]) versus TohamaI (labeled Tohama) (**, P < 0.01 [by a 1-tailed t test]) (n = 4 mice per group). (B) Mouse survival after a high-dose infection (3 × 10⁸ CFU per mouse) with B. pertussis TohamaI/mutAC versus the parental TohamaI strain (*, P < 0.05 [by Mantel-Cox test]) (n = 4 mice per group) (the 95% confidence interval is shown in gray). (C) Mouse weight changes after infection for mice shown in panel B. The experiment was repeated twice, with similar results.