Fig. 3

Real-time qRT-PCR analysis of the sstFEG, bceAB, and bceRS. The data were normalized to the housekeeping gene parC transcript [18]. The relative expression levels represent the mean ± SD for three independently isolated RNA samples. (a) The comparison of gene expression in the presence (Bac [2 μg/mL]) or absence of bacitracin. The concentration of bacitracin at 2 μg/mL was tested that could not kill S. suis cells rapidly. (b, c, d) The expression changes of sstFEG, bceAB and bceRS in different deletion mutant under the bacitracin stress. Several-fold changes represent the relative gene expression in the wild-type and mutant strains cultured in the presence (Bac [2 μg/mL]) of bacitracin