High-throughput X-ray techniques and drug discovery.

In the past two decades the promise of structure-based drug design has continued to attract significant interest from the pharmaceutical industry. The initial wave of enthusiasm in the late eighties resulted in some notable successes, for example, the crystal structures of HIV protease and influenza neuraminidase were used to design Viracept and Relenza, both drugs currently used in anti-viral therapy (1, 2). However, although structure-based design methods continued to be developed, the approach became largely eclipsed in the early nineties by other technologies such as combinatorial chemistry and high-throughput screening (HTS) which seemed to offer a more effective approach for drug discovery. The goal of obtaining a crystal structure of the target protein, particularly in complex with lead compounds was regarded as a resource-intensive, unpredictable and slow process. During that period it was clear that protein crystallography was unable to keep pace with the other drug discovery technologies being performed in a highthroughput mode.