FIG 12.

Full-length WT ToxT degradation is inhibited by the addition of linoleic acid after shift to virulence-repressing conditions. (A) V. cholerae was grown under virulence-inducing conditions (LB, pH 6.5, 30°C, shaking) for 3 h to induce the production of WT ToxT from pBAD33. Samples were resuspended under virulence-repressing growth conditions (LB, pH 8.5, 37°C, shaking) with the addition of DMSO or 320 μM linoleic acid. Equivalent culture volumes were taken at each time point to monitor the degradation of full-length ToxT. Full-length ToxT migrates to ∼32 kDa (arrow). WT ToxT degradation over time in the absence of linoleic acid is shown in lanes 2 to 5, and WT ToxT degradation over time with the addition of linoleic acid is shown in lanes 6 to 9. (B) Quantification of band intensities from blot shown in panel A was performed using ImageJ software. Graph represents percentages of ToxT remaining after shift to virulence-repressing conditions compared to the amounts at time zero. WT ToxT was 75% degraded by 30 min after shift to virulence-repressing growth conditions, while ToxT in the presence of linoleic acid persisted to a greater extent. Blot shown is representative of at least 3 separate experiments.