[1] Department of Biochemistry, University of Cambridge, Cambridge, CB2 1GA
[2] EMBLEBI The European Bioinformatics Institute, Hinxton, Cambridge, CB10 1SD, Wellcome Trust Genome Campus
[3] Department of Biochemistry, University of Wisconsin, Madison, WI, 53706-1544
[4] Unite de Bioinformatique Structurale, Institut Pasteur, F-75015 Paris
[5] Biotechnology Division (831), Gaithersburg, MD 20899-8314, NIST, 100 Bureau Drive
[6] Rutgers University, The State University of New Jersey, Department of Chemistry and Chemical Biology, Piscataway, NJ, 08854-8087
[7] Center for Advanced Research in Biotechnology, Rockville, MD, 20850