1. Center for Structural Biology, Vanderbilt University , 465 21st Ave S, 5140 MRB3 , Nashville , TN 37240 , USA
2. Department of Chemistry , Vanderbilt University, 7330 Stevenson Center , Station B 351822 , Nashville , TN 37235 , USA
3. Institute for Drug Discovery, University of Leipzig , Brüderstr. 34, D-04103 Leipzig , Germany
4. Institute for Medical Physics and Biophysics, University of Leipzig , Härtelstr. 16-18 , D-04107 Leipzig , Germany
5. Faculty of Chemistry, University of Gdańsk , Ul. Wita Stwosza 63, 80-308 Gdańsk , Poland