FIG 4.
Validation of serum survival defects in ΔrfaH and Δlpp mutants. Total bacterial viable count of K. pneumoniae strains and key mutants following incubation with 66% pooled normal human serum (see Materials and Methods). The detection limit of the assay is 2 × 103 viable cells per ml. Overall statistical significance was determined by two-factor repeated measures ANOVA (P < 0.0001 for all strains), mutants were compared to the wild type (WT) at t = 180 by single-factor ANOVA and Dunnett’s test at t = 180 (**, P < 0.01). For ATCC 43816 WT and mutants, n = 5; for all other strains, n = 3.