1. Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K.
2. Now: Department of Biochemistry, School of Medicine, Emory University, 1510 Clifton Rd NE, Atlanta, Georgia 30322, United States
3. Now: Institute of Chemical, Environmental and Bioscience Engineering, Technische Universität Wien, Gumpendorferstr. 1A, Vienna 1060, Austria
4. Now: Randall Centre for Cell & Molecular Biophysics, King’s College London, Great Maze Pond, London SE1 1UL, U.K.