1. Department of Biochemical Engineering; University College London, Bernard Katz Building; Gordon Street London WC1H 0AH UK
2. Department of Structural and Molecular Biology; University College London; Gower Street WC1E 6BT UK
3. Department of Biocatalysis and Isotope Chemistry; Almac; 20 Seagoe Industrial Estate Craigavon Northern Ireland (UK
4. Department of Chemistry; University College London; 20 Gordon Street London WC1H 0AJ UK