FIG 2.
Interactions of fluorescein-labeled SLA80 with dengue virus NS5. Fluorescence titrations of fluorescein-labeled SLA80 with DENV3 NS5 (λex = 480 nm; λem = 520 nm) were carried out by using standard buffer (100 mM NaCl, 50 mM Tris [pH 7.5], 10% glycerol, and 1 mM DTT at 10°C) containing the following different MgCl2 concentrations: 0 mM, 0.4 mM, 1.0 mM, 1.3 mM, and 2.0 mM. The concentration of fluorescein-labeled SLA80 is 1.5 × 10−8 M. The solid lines are nonlinear least-squares fits of the titration curve with a K of 1.8 × 106 M−1 (0 mM MgCl2), a K of 2.2 × 106 M−1 (0.4 mM MgCl2), a K of 5.5 × 106 M−1 (1.0 mM MgCl2), a K of 2.3 × 106 M−1 (1.3 mM MgCl2), and a K of 1.8 × 106 M−1 (2.0 mM MgCl 2).