The structure of ibuprofen bound to cyclooxygenase-2.
Orlando, B.J., Lucido, M.J., Malkowski, M.G.(2015) J Struct Biol 189: 62-66
- PubMed: 25463020 
- DOI: https://doi.org/10.1016/j.jsb.2014.11.005
- Primary Citation of Related Structures:  
4PH9 - PubMed Abstract: 
The cyclooxygenases (COX-1 and COX-2) catalyze the rate-limiting step in the biosynthesis of prostaglandins, and are the pharmacological targets of non-steroidal anti-inflammatory drugs (NSAIDs) and COX-2 selective inhibitors (coxibs). Ibuprofen (IBP) is one of the most commonly available over-the-counter pharmaceuticals in the world. The anti-inflammatory and analgesic properties of IBP are thought to arise from inhibition of COX-2 rather than COX-1. While an X-ray crystal structure of IBP bound to COX-1 has been solved, no such structure exists for the cognate isoform COX-2. We have determined the crystal structure of muCOX-2 with a racemic mixture of (R/S)-IBP. Our structure reveals that only the S-isomer of IBP was bound, indicating that the S-isomer possesses higher affinity for COX-2 than the R-isomer. Mutational analysis of Arg-120 and Tyr-355 at the entrance of the cyclooxygenase channel confirmed their role in binding and inhibition of COX-2 by IBP. Our results provide the first atomic level detail of the interaction between IBP and COX-2.
Organizational Affiliation: 
Department of Structural Biology, The State University of New York at Buffalo and the Hauptman-Woodward Medical Research Institute, 700 Ellicott Street, Buffalo, NY 14203, USA.