FIGURE 7.

Cytotoxicity of ExoU homologs. A, HeLa cells were transfected with ExoU expression constructs and analyzed for release of lactate dehydrogenase as a measure of cell death. Results were normalized to treatment with Triton X-100 (100% cell death) and mock-transfected cells (0% cell death). Vector indicates transfection of pcDNA3.1 NT-GFP vector without insert. Each assay was performed in triplicate; values are means, and error bars represent S.E. *, p < 0.001. B, same GFP-tagged constructs shown in A were transfected into HeLa cells, which were subsequently analyzed for expression of the resulting proteins with anti-GFP antibody. MW denotes the molecular weight markers.