The EVH2 domain is responsible for the ssDNA-annealing activity and the ssDNA-catenation. (A) ssDNA annealing activities of EVL(222–418). EVL, EVL(1–221) or EVL(222–418) was first incubated with ssDNA (0.2 µM), followed by the addition of a complementary ssDNA. The reactions were conducted at 30°C for 8 min. Lane 1 indicates a control experiment without protein, and lanes 2–4, lanes 5–7 and lanes 8–10 indicate the experiments with EVL, EVL(1–221) and EVL(222–418), respectively. The EVL, EVL(1–221) and EVL(222–418) concentrations were 0.1 µM (lanes 2, 5 and 8), 0.5 µM (lanes 3, 6 and 9) and 1 µM (lanes 4, 7 and 10). (B) Graphical representation of the experiments shown in panel A. The band intensities of the annealed products were quantified, and the average values of three independent experiments are shown with the standard deviation values. Closed circles, open circles and open triangles indicate experiments with EVL, EVL(222–418) and EVL(1–221), respectively. (C) Catemer formation with the EVL(222–418) fragment. Lane 1 indicates a control experiment without protein. Lanes 2 and 5 indicate the experiments with EVL. Lanes 3 and 6 indicate the experiments with EVL(1–221). Lanes 4 and 7 indicate the experiments with EVL(222–418). Lanes 5–8 indicate the experiments in the presence of Topo I (0.4 nM). The ϕX174 circular ssDNA molecule is indicated by css.