Fig. 1.

Ligand-bound X-ray co-crystal structures of active flavivirus NS2B-NS3 proteases. (a) Dengue protease serotype 3 with the covalently bound aldehyde ligand 1 (3U1I) (Noble et al. 2012). (b) West Nile protease with the covalently bound boronate ligand 2 (5IDK) (Nitsche et al. 2017). (c) Zika protease with the covalently bound boronate ligand 2 (5LC0) (Lei et al. 2016). (d) Superimposition of active conformations of NS2B-NS3 proteases from dengue (3U1I), West Nile (5IDK) and Zika (5LC0) viruses. Co-crystallised ligands have been removed from the structures. Residues of the catalytic triad are indicated. Residues marked with an asterisk indicated NS2B. This figure has been generated with Chimera (Pettersen et al. 2004)