1. Department of Cell and Chemical Biology, Leiden University Medical Centre, 2300 RC Leiden, The Netherlands
2. Leiden Institute of Chemistry, Leiden University, 2333 CC Leiden, The Netherlands
3. School of Chemistry, University of Bristol, Bristol, BS8 1QU, UK
4. Department of Chemistry and Pharmaceutical Sciences, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands
5. School of Biochemistry, University of Bristol, Bristol, BS8 1TD, UK