1. Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
2. Institute of Biochemistry and Molecular Medicine, University of Bern, Bühlstrasse 28, 3012 Bern, Switzerland
3. Department of Chemistry, University of Warwick, Coventry CV4 7AL, U.K.
4. Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, U.K.
5. Department of BioMedical Research, Mass Spectrometry and Proteomics Laboratory, University of Bern, Inselspital, 3010 Bern, Switzerland