FIG. 7.
Colonization of the mouse respiratory tract by bipA deletion mutants derived either from wild-type B. pertussis GMT1 (A) or from GMT1i (B). Groups of mice were inoculated intranasally with 50 μl of PBS containing 106 CFU of one of the experimental strains (A, GMT1 and GMT1-DBA; B, GMT1i and GMT1i-DBA). At days 0 (three mice at least) and 8 (five mice at least), the animals were sacrificed, and colonization at various sites of the respiratory tract was determined. Error bars represent 1 standard deviation. The dashed line indicates the lower limit of detection. The asterisks denote a statistically significant difference (**, P < 0.01) between the two specified groups.