Figure 7.

The COOH‐terminal region of VipA is essential, but not sufficient, for VipA‐mediated actin polymerization. In vitro actin polymerization assays were carried out in the presence of 1 μmol/L monomeric actin (10% Pyrene‐actin) and purified wild‐type or mutant His₆‐VipA. Fluorescence (expressed in Arbitrary Units, AU) was measured over time after initiation of polymerization (at t = 3 min). (A) Samples were preincubated with 100 nmol/L of each purified His₆‐VipA variant. (B) Samples were preincubated with the indicated concentrations of each purified His₆‐VipA variant. Curves representative of at least three independent experiments are shown.