1. Department of Chemistry & Nano-Science Center, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark
2. Novo Nordisk Foundation Centre for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen, Denmark
3. Department of Physical Chemistry, Lund University, SE-221 00 Lund, Sweden
4. Department of Biotechnology and Biomedicine, Technical University of Denmark, Building 221, Søltofts Plads, DK-2800 Lyngby, Denmark