University of Oxford Department of Biochemistry
Resolving structural details of membrane receptors is still a major challenge, not least because of the difficulties of expression, crystallization and their size. Since membrane protein secondary structure can be modeled for many cases, we have been devising solid-state NMR methods for determining high resolution (sub-Å) details of information-rich sites within membrane receptors (Watts, A., 2005. Nature Reviews Drug Discovery, 4, 555-568). In particular, we have resolved new information about ligand (drug, neurotransmitter or solute) binding sites, and related all this information to functional descriptions.
Our recent focus has been on the neurotensin receptor (NTS1) which we have expressed in E. coli in structural biology amounts (Attrill et al, 2009, J. Express & Purif, 64, 32-38) in a functionally competent form for structural studies, some of which involve single molecule approaches for bionanotechnological and drug design applications.
NTS1 is now available highly purified monodispersed in detergent and in a ligand-binding form. One approach to monitoring ligand binding has been to develop a novel surface plasmon resonance method for tagging the natural ligand, neurotensin (13-mer peptide), to the chip and monitoring protein binding (Harding et al., 2006, Euro. Biophys. J., 35, 709-712). Fluorescently tagged NTS1 has also been used in fluorescence resonance energy transfer methods to resolvelong-rangee information of protein-protein signalling (Harding, et al., 2009, Biophsy. J., 96, 964-973).
Watts, A. (2012) Exploiting magnetic resonance spectral anisotropy averaging to gain biological details in biomembranes. Encyclopaedia of Magnetic Resonance – Historical Perspectives (E. D. Becker, Editor) Wiley Interscience (in press).
Higman, V. and Watts, A. (2012) “CHAPTER 13 Recent Developments in Biomolecular Solid-State NMR”, in Recent Developments in Biomolecular NMR, eds M. Clore and J. Potts (in press)
Oates, J., Faust, B., Attrill, H., Harding, P., Orwick, M., Watts, A. (2012) The role of cholesterol on the activity and stability of neurotensin receptor 1. BBA – Biomembranes, 1818, 2228-33.
Goddard, A. and Watts, A. (2012) Contributions of fluorescence techniques to understanding G protein-coupled receptor dimerisation. Biophysical Review. (in press) doi: 10.1007/s12551-012-0073-z
Goddard, A. and Watts, A. (2012) Regulation of G protein-coupled receptors by palmitoylation and cholesterol. BMC Biology, 10, 27-30.
Orwick, M., Judge, P., Procek, J., Lindholm, L., Graziadei, A., Engel, A., Grobner, G., Watts, A. (2012) Detergent-free formation and physico-chemical characterization of nanosized lipid-polymer complexes – Lipodisq. Angewante Chemie, 51, 1-6.
Patil, A., Premaruban, T., Berthoumieu, O., Watts, A., Davis, J. (2012) Engineered Bacteriorhodopsin: A Molecular Scale Potential Switch. Chem. Eur. J., 18, 5632-36.
Pike, K.J., Kemp, T.F., Takahashi, H., Day, R., Howes, A.P., Kryukov, E.V., MacDonald, J.F., Collis, A.E.C., Bolton, D.R., Wylde, R.J., Orwick, M., Kosuga, K., Clark, A.J., Idehara, T., Watts, A., Smith, G.M., Newton, M.E., Dupree, R., Smith, M.E. (2012) A spectrometer designed for 6.7 and 14.1 T DNP-enhanced solid-state MAS NMR using quasi-optical microwave transmission, J. Mag. Res., 215, 1-9.
Berthoumieu, O., Patil, A., Wang, X., Aslimovska, L., Davis, J., and Watts, A. (2012) Molecular scale conductance photoswitching in engineered bacteriorhodopsin. Nano Letters, 12, 899–903.
Patil, A., Premaruban, T., Berthoumieu, O., Watts, A., Davis, J. (2012) Enhanced photocurrent in engineered bacteriorhodopsin monolayer films.J. Phys. Chem. B, 116 , 683–689.