1. Department of Molecular Biology and BiotechnologyKrebs InstituteUniversity of Sheffield Sheffield S10 2TN UK
2. School of ChemistryCardiff University Cardiff CF10 3AT UK
3. Department of Biochemistry and Molecular BiologyIndiana University School of Medicine Indianapolis IN 46202 USA
4. ENSCO, Inc. Melbourne FL 32940 USA
5. Structural Biology GroupESRF-The European Synchrotron, CS40220 38043 Grenoble, Cedex 9 France
6. Manchester Institute of Biotechnology Manchester M1 7DN UK
7. European Molecular Biology Laboratory, Grenoble Outstation CS90181 38042 Grenoble, Cedex 9 France