1. Department of Biosciences; University of Milan; Via Celoria 26, 20133, Milan Italy
2. A.V. Shubnikov Institute of Crystallography of Federal Scientific Research Centre “Crystallography and Photonics” of Russian Academy of Sciences; Leninsky prospect 59, 119333, Moscow Russia
3. A.N. Frumkin Institute of Physical Chemistry and Electrochemistry of Russian Academy of Sciences; Leninsky Prospect 31, 119071, Moscow Russia
4. N.N. Semenov Institute of Chemical Physics of Russian Academy of Sciences; Kosygina str. 4, 119991, Moscow Russia
5. European Molecular Biology Laboratory; EMBL Hamburg Unit, c/o DESY; Notkestrasse 85, D-22607, Hamburg Germany
6. Department of Structural Biochemistry; Max-Planck Institute of Molecular Physiology; Otto-Hahn-Str. 11, 44227, Dortmund