CdtR Regulates TcdA and TcdB Production in Clostridium difficile
Fig 2
a–c, Western immunoblot using CDTa-specific and cross-reactive Ib-specific antibodies and precipitated supernatants from the strains indicated. CD37 (non-toxigenic), V = vector control, R+ = cdtR complemented. The arrows indicate the 48 kDa CDTa and 99 kDa CDTb proteins. d–f, CDT activity assessed by ADP-ribosyltransferase assay. Samples were separated by SDS-PAGE and biotinylated (ADP-ribosylated) actin detected by HRP-streptavidin. Relative CDT activity was assessed by densitometry compared to the non-toxigenic control strain CD37. A = actin, A-A = ADP-ribosylated actin. Data represent the mean ± SEM (n = 3). *, p ≤ 0.05.