1. Department for NMR-based Structural Biology Max Planck Institute for Biophysical Chemistry Am Faßberg 11 37077 Göttingen Germany
2. Center for Biostructural Imaging of Neurodegeneration University Medical Center Göttingen Von-Siebold-Str. 3A 37075 Göttingen Germany
3. Department of Neurology University Medical Center Göttingen Waldweg 33 37073 Göttingen Germany
4. Institute of Physical Biology Heinrich Heine University Düsseldorf Universitätsstraße 1 40225 Düsseldorf Germany