Figure 2.

NS3-4A protease domain of PDB structure 1RTL with co-crystallized ligand CPX (yellow) [32] and a second ligand, SCH 446211 (light blue), taken from the superimposed PDB structure 2FM2 [30]. The protease binding pocket from structure 1RTL is shown as a transparent surface patch. The residues V36 and T54 are depicted as stick-and-ball models, located in the parallel β-strands β1 and β3 of an anti-parallel β-sheet (dark blue).