Figure 3.
NS5A-D2 interacts with NS5BΔ21. a, superposition of methyl-TROSY spectra of U-15N,2H-,Ile δ1-13C1H3-labeled NS5BΔ21 (40 μm) recorded in the presence of increasing concentrations (0, 20, 40, 80, 200, and 400 μm) of unlabeled NS5A-D2. b, 1H,13C combined CSPs observed in the NS5B–NS5A-D2 (1:2 molar ratio in a) spectrum mapped, from yellow (0 ppm) to red (0.018 ppm), onto the Ile δ1 methyl groups of the NS5B structure (PDB code 2XXD). The CSP for Ile-419 is 0.031 ppm (above the defined upper limit) and is highlighted. Methyl groups that were not observed are shown as black dotted spheres. The figure was prepared using PyMOL. c, titration curves corresponding to the experiments in a. 1H,13C combined CSPs observed for Ile-419, Ile-23, and Ile-363 residues in NS5BΔ21 are plotted as a function of increasing concentrations of NS5A-D2. Corresponding dissociation constants were obtained by fitting the experimental data to the theoretical equation corresponding to a reversible complex.