1. Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99354, United States
2. Chemical and Biological Signature Sciences, Pacific Northwest National Laboratory, Richland, Washington 99354, United States
3. Biological Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99354, United States
4. Center for Structural Biology of Infectious Diseases, Consortium for Advanced Science and Engineering, University of Chicago, Chicago, Illinois 60637, United States
5. Structural Biology Center, X-ray Science Division, Argonne National Laboratory, Argonne, Illinois 60439, United States
6. Biosciences Division, Argonne National Laboratory, Argonne, Illinois 60439, United States