Figure 5

The MKD site of CiaD is necessary for cellular invasion and IL-8 secretion. (A) Schematic representation of the CiaD wild-type protein, the CiaD MAP kinase docking motif (ΔMKD site) mutant protein, and CiaD proline directed-phosphorylation site (Δ(S/T)P) mutant protein. (B) The MKD site of CiaD is required for C. jejuni to induce maximal IL-8 secretion from INT 407 cells. The value obtained from cells only was subtracted from all other values. (C) The MKD site of CiaD is required for maximal C. jejuni invasion of INT 407 cells. The asterisks indicate a significant difference compared to the C. jejuni wild-type strain, as judged by one-way ANOVA followed by post-hoc Tukey’s analysis (P < 0.05). Error bars represent ± SEM of N = 12 samples from 3 independent experiments.