1. Institute of Microbiology; Eigenössische Technische Hochschule (ETH) Zurich; Vladimir-Prelog-Weg 1-5/10 8093 Zurich Switzerland
2. Chemistry & Biochemistry Department; University of California Santa Cruz; 1156 High Street 95064 Santa Cruz California USA
3. Department of Chemistry; Simon Fraser University; 8888 University Drive Bumaby BC V5A 1S6 Canada