Abstact

The crystal structure of the complex of human recombinant aldose reductase (AR) with zenarestat, one of its potent inhibitors, has been solved at 2.5 A resolution. Zenarestat fits neatly in the hydrophobic active site and induces unique and dramatic conformational changes. For example, the benzene ring of zenarestat occupies a gap in the side chains of Leu300 and Trp111 that interact directly and forms a CH-pi interaction in the native holoenzyme. As a result, the benzene ring of the inhibitor and these side chains form a CH-pi-pi interaction. Such structural information is key to understanding the mode of action of this class of inhibitors and for rational design of better therapeutics.