1. Department of Microbiology; University of Kaiserslautern; Paul-Ehrlich Straße 23 D-67663 Kaiserslautern Germany
2. Molecular Genetics Group; Groningen Biomolecular Sciences and Biotechnology Institute; Centre for Synthetic Biology; University of Groningen; Nijenborgh 7 9747 AG Groningen The Netherlands
3. Stiftung Alfried Krupp Kolleg Greifswald; D-17487 Greifswald Germany