Fig 2.

All three mutants are defective for growth in macrophages. (A) Human MDMs were infected with opsonized wild-type or mutant bacteria at an MOI of 20:1, and viable intracellular bacteria were quantified at 2 and 20 h postinfection by enumeration of CFU. The data shown are the means and SD of triplicate samples from one experiment representative of three. **, P < 0.01 versus Schu S4. (B) Similar to panel A, except MDMs were infected at an MOI of 100:1 in medium supplemented with heat-inactivated human serum. **, P < 0.01 versus Schu S4. (C) J774A.1 cells were infected with unopsonized bacteria at an MOI of 200:1, and viable intracellular bacteria were quantified at 2 and 26 h postinfection. The data are the means and SD from one experiment representative of three. **, P < 0.01 versus Schu S4; +, P < 0.05 versus the pdpC mutant.