Abstract
Single-crystal neutron diffraction data were collected at 20 K to a resolution of 1.05 Åon a crystal of the inverse formyl peptide receptor agonist cyclosporin H, CsH, (crystal form II, CsH-II) on the Laue diffractometer VIVALDI at the Institut Laue-Langevin (Grenoble). The solvent structure and hydrogen bonding network of CsH-II have been unambiguously determined by single-crystal neutron diffraction; the agreement factor R(F2) is 13.5% for all 2726 reflections. All hydrogen atom positions, including methyl-group orientations, have been determined by crystallographic refinement. The neutron structure of cyclosporine provides unique and complementary insights into methyl orientation, hydrogen-bonding, and solvent interactions that are not available from X-ray analysis alone.
Original language | English |
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Pages (from-to) | 470-480 |
Number of pages | 11 |
Journal | Journal of Chemical Crystallography |
Volume | 41 |
Issue number | 4 |
DOIs | |
State | Published - Apr 2011 |
Funding
Acknowledgments We gratefully acknowledge the ILL for the provision of beamtime. We thank Professor Jon Cooper for his help and interest in the early stages of this study. We thank Ray Simpson for depicting the main chain trace shown in the Index Abstract figure. This research at Oak Ridge National Laboratory’s Center for Structural Molecular Biology (CSMB) was supported by the Office of Biological and Environmental Research, using facilities supported by the US Department of Energy, managed by UT-Battelle, LLC under contract No.DE-AC05-00OR22725. This research was supported in part by an appointment to the ORNL Postdoctoral Research Associates Program at the Oak Ridge National Laboratory, sponsored by the US Department of Energy and administered by the Oak Ridge Institute for Science and Education.
Keywords
- Cyclosporin H
- Hydrogen bonding
- Laue diffraction
- Neutron structure
- Water hydrogens