1. Department of Physical Biochemistry, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany
2. Infection Biology Unit, German Primate Center, Kellnerweg 4, 37077 Göttingen, Germany
3. Faculty of Biology and Psychology, University of Göttingen, Wilhelm-Weber-Str. 2, 37073 Göttingen, Germany