Figure 4. The E3 ligase activity of EHEC NleL down modulates EPEC pedestal formation.

HeLa cells were infected at a multiplicity of infection of 100 with wild type EPEC, or EPEC harboring plasmid expressing wild-type EHEC NleL or NleL^C753A. Cells were infected for 4 hours. (A) Bacteria were visualized by staining with an anti-EPEC LPS antibody (green). Actin was detected with a Texas Red Phalloidin (red). (B) The number of micro-clusters of pedestals on HeLa cells were counted and were grouped into clusters having 1–10 pedestals, 11–20 pedestals and >20 pedestals. Quantitative analysis includes three independent experiments. A minimum of 300 cells were counted from each experiment with standard deviation shown as error bars.