1. Chemical
Biology Center (KBC), Institute of Chemistry, Umeå University, Umeå, 90187, Sweden
2. Max Planck Institute of Molecular Physiology, Department of Chemical Biology, Dortmund 44227, Germany
3. Center
for Integrated Protein Science Munich, Chemistry Department, Technische Universität München, Lichtenbergstr. 4, 85748 Garching, Germany