FIG. 5.

Interactions between the putative components of the EPEC TTS apparatus. (A) Purified GST-Esc fusion proteins were analyzed by 12% SDS-PAGE followed by CBB staining. Arrowheads indicate presumed bands corresponding to the respective GST fusion proteins. Lane M indicates the size markers. (B) Interactions of Esc proteins in a GST pulldown assay. Whole-cell extracts from E. coli expressing EscD or EscF tagged with the V5 epitope (EscD-V5 or EscF-V5) were incubated with each agarose-immobilized GST-Esc protein. Proteins bound to the beads were resolved by 14% SDS-PAGE and then analyzed by Western blotting using anti-V5 monoclonal antibodies.