“…Increases in efficiency and reliability of computational tools have enabled virtual screening to become a routine method in pharmaceutical drug discovery, complementing in vitro highthroughput screening (Schneider and Bohm, 2002;Shoichet et al, 2002;Waszkowycz, 2002;Jorgensen, 2004). Inhibitors have been identified by computational screening of compound databases for protein tyrosine phosphatase-1B (Doman et al, 2002), nuclear hormone receptors (Schapira et al, 2000(Schapira et al, , 2001, human carbonic anhydrase (Gruneberg et al, 2002), thymidylate synthase (Shoichet et al, 1993), integrin alphavbeta3 (Zhou et al, 2006), acetylcholinesterase (Mizutani and Itai, 2004), glycogen synthase kinase-3beta (Polgar et al, 2005), and thrombin (Massova et al, 1998;Bohm et al, 1999;Fox and Haaksma, 2000;Howard et al, 2006). Typically, structure-based virtual screening (in which ligand candidates are docked into the atomic structure of a protein's binding site and evaluated by the resulting protein interactions) and ligand-based screening (in which ligand (www.interscience.wiley.com) DOI:10.1002/jmr.942 candidates are aligned and scored for similarity to a prototypical known ligand) are used independently (Oprea and Matter, 2004;McGaughey et al, 2007).…”