FIG. 6.
Guinea pig challenges with wild-type (WT) Ames or purH mutant strains. (A) Competitive index generated from the guinea pig assay for comparison of the in vivo fitness of purH mutant strains to that of the wild-type Ames strain (P < 0.0001). Guinea pigs were challenged intramuscularly with approximately 1 × 103 spores consisting of approximately equal ratios of wild-type and mutant spores. (B) Guinea pigs were challenged intramuscularly with approximately 1 × 103 wild-type Ames, purH::Kan, or ΔpurH spores (P, <0.0001 for both the percentage of animals surviving and the survival curve), (C) Guinea pigs were challenged intraperitoneally with approximately 4 × 104 wild-type Ames or ΔpurH spores (P, 0.025 for the percentage of animals surviving and 0.04 for the survival curve). (D) Guinea pigs were challenged intraperitoneally with approximately 1.6 × 105 CFU of wild-type Ames or purH::Kan bacilli (P, 0.008 for the percentage of animals surviving and 0.003 for the survival curve).