1. Department of Microbiology, University of Helsinki, P.O. Box 56, Viikki Biocenter, Viikinkaari 9, FI-00014 Helsinki, Finland
2. Drug Research Program, Division of Pharmaceutical Chemistry and Technology, Faculty of Pharmacy, University of Helsinki, P.O. Box 56, Viikinkaari 5 E, FI-00014 Helsinki, Finland
3. Research Program in Structural Biology and Biophysics, Institute of Biotechnology, University of Helsinki, P.O. Box 65, FI-00014 Helsinki, Finland
4. Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
5. Collection des Cyanobactéries, Département de Microbiologie, Institut Pasteur, 28 Rue du Docteur Roux, 75724 Cedex 15, 75015 Paris, France
6. VERIFIN, Department of Chemistry, University of Helsinki, P.O. Box 55, FI-00014 Helsinki, Finland