1. Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
2. School of Chemistry, University of Leeds, Leeds LS2 9JT, United Kingdom
3. School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
4. Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, United States