FIGURE 4.

Amino acid specificity of RI-10 binding to the extracellular domain of CsrS. The data represent fold increase in transcript abundance for four CsrRS-regulated genes in GAS grown in the presence of 300 nm peptide (RI-10 amino acid substitutions; Table 4) compared with that for GAS grown in the absence of peptide. * denotes three of four and ** denotes four of four virulence factors for which expression in the presence of peptide is significantly different (p < 0.05) from that for GAS grown in the presence of RI-10.