FIG 5.

Biased impact of natural transformation on the virulence of the hypertransformable pneumococcal isolates. (A) The contribution of the transformation to the virulence (lung infectivity) of the 18 selected S. pneumoniae isolates with different transformability capacities during the coinfection of each isolate and its ΔcomGC mutant. The experimental design and result display are the same as in Fig. 4B except for the use of CD1 mice and a 48-h infection duration. (B) The lung infectivity levels of the 18 S. pneumoniae isolates. The total CFU value of the wild-type strain in the lungs from each mouse is presented as in Fig. 4C.