1. Helmholtz Institute for Pharmaceutical Research Saarland (HIPS) Helmholtz Center for Infection Research, and Department of Pharmacy Saarland University Campus Building E8.1 66123 Saarbrücken Germany
2. Helmholtz Centre for Infection Research Department of Microbial Drugs Braunschweig Germany
3. Lehrstuhl für Organische Chemie I Technische Universität München Lichtenbergstrasse 4 85747 Garching Germany
4. Shandong University-Helmholtz Joint Institute of Biotechnology State Key Laboratory of Microbial Technology School of Life Science Shandong University Qingdao P. R. China