1. Department of Microbial Natural Products
2. Helmholtz Institute for Pharmaceutical Research Saarland
3. 66123 Saarbrücken
4. Germany
5. Department of Drug Design and Optimization
6. Pharmaceutical and Medicinal Chemistry
7. Saarland University
8. Helmholtz Centre for Infection Research
9. 38124 Braunschweig
10. Workgroup Structural Biology of Biosynthetic Enzymes