1. Department of Chemistry, University of Turku, Vatselankatu 2, FI 20014 Turku, Finland
2. Department of Cellular and Molecular Medicine, School of Medicine, University of California, San Diego, La Jolla, California 92093, United States
3. Turku Centre for Biotechnology, University of Turku, Åbo Akademi University, Tykistökatu 6, FI 20520 Turku, Finland