Affiliation: | 1. Research Program in Structural Biology and Biophysics, Institute of Biotechnology, University of Helsinki, P.O. Box 65, Helsinki FIN-00014, Finland;2. Macromolecular Crystallography Laboratory, National Cancer Institute, Frederick, MD 21702, USA;3. Basic Science Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research, Frederick, MD 21702, USA |