Figure 7

GBS susceptibility to penicillin increases in the absence of CpsA and Psr. GBS strains were grown in THY medium, normalized to OD600: 0.01 in PBS and treated with 3 μg/mL penicillin for 24 h. (A) Treated (Red) and untreated (Blue) samples were then serially diluted and plated on THY plates and counted. Statistical analysis represents significance between untreated and treated cells for each strain. (B) Log CFU killed was calculated for each sample taking Log10 (untreated/treated). Significance was determined by comparing log CFU killed of each strain to that of wild type GBS. Values represented are averages of four biological replicates. * p < 0.05, ** p < 0.005.