Figure 3.

PerR regulation of sodB in C. jejuni. (A) De-repression of sodB by a perR mutation. A perR mutation de-repressed sodB transcription, and the level of sodB transcription was completely restored by complementation. The sodB promoter activity was determined in MEMα with or without 40μM FeSO₄. The results show the standard deviations of three different experiments. Statistical analysis was performed with a Student's t-test using GraphPad Prism 6. ^****P < 0.0001; perR+, a perR complementation strain. (B) rPerR binding to the sodB promoter. Cy3-labeled PCR probes of a sodB promoter region were incubated with rPerR at different concentrations that are indicated above the gel. The assay was conducted in a 6% polyacrylamide gel under native conditions. (C) A putative PerR-binding site in the sodB promoter. The binding site was predicted based on the consensus PerR-binding sequence in C. jejuni (Kim et al., 2011).