1. Chemical
Biology Laboratory, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland 21702, United States
2. Chemical
Biology Laboratory, National Cancer Institute, Frederick, Maryland 21702, United States
3. Macromolecular
Crystallography Laboratory, National Cancer Institute, Frederick, Maryland 21702, United States
4. Laboratory
Animal Sciences Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer
Research, Frederick, Maryland 21702, United States