1Center for Bioinformatics and Computational Biology, University of Delaware, Newark,
DE 19711, USA,
2Center for Computational Pharmacology, University of Colorado Denver School of Medicine,
Aurora, CO 80045, USA,
3The MITRE Corporation, Bedford, MA 01730, USA,
4Structural and Computational Biology Group, Spanish National Cancer Research Centre,
Madrid E-28029, Spain,
5National Center for Biotechnology Information, National Library of Medicine, Bethesda,
MD 20892, USA and
6Department of Biology, North Carolina State University, Raleigh, NC 27695, USA