Download MendeleyCombined X-ray, NMR, and kinetic analyses reveal uncommon binding characteristics of the hepatitis C virus NS3-NS4A protease inhibitor BI 201335.
Lemke, C.T., Goudreau, N., Zhao, S., Hucke, O., Thibeault, D., Llinas-Brunet, M., White, P.W.(2011) J Biol Chem 286: 11434-11443
- PubMed: 21270126
- DOI: https://doi.org/10.1074/jbc.M110.211417
- Primary Citation of Related Structures:
3P8N, 3P8O - PubMed Abstract:
Hepatitis C virus infection, a major cause of liver disease worldwide, is curable, but currently approved therapies have suboptimal efficacy. Supplementing these therapies with direct-acting antiviral agents has the potential to considerably improve treatment prospects for hepatitis C virus-infected patients. The critical role played by the viral NS3 protease makes it an attractive target, and despite its shallow, solvent-exposed active site, several potent NS3 protease inhibitors are currently in the clinic. BI 201335, which is progressing through Phase IIb trials, contains a unique C-terminal carboxylic acid that binds noncovalently to the active site and a bromo-quinoline substitution on its proline residue that provides significant potency. In this work we have used stopped flow kinetics, x-ray crystallography, and NMR to characterize these distinctive features. Key findings include: slow association and dissociation rates within a single-step binding mechanism; the critical involvement of water molecules in acid binding; and protein side chain rearrangements, a bromine-oxygen halogen bond, and profound pK(a) changes within the catalytic triad associated with binding of the bromo-quinoline moiety.
Organizational Affiliation:
Boehringer Ingelheim (Canada) Ltd., Research and Development, Laval, Quebec, Canada. christopher.lemke@boehringer-ingelheim.com
