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Research Overview

Nucleic Acids

We are involved in a number of different approaches for the study of nucleic acid structure in crystals, fibres and solution. These studies include (i) low resolution studies of the assembly and disassembly of telomeric quadruplex-forming DNA sequences that form quadruplexes, (ii) fibre diffraction studies of DNA polymorphism, (iii) single crystal studies of DNA oligonucleotoides and complexes with anti-cancer drugs. These studies involve a strong collaboration with Reading University

Amyloid forming peptides

Here we use X-ray and neutron fibre diffraction techniques to study the conformation of amyloid forming peptides. Amyloid type structures are implicated in a wide range of diseases including Alzheimer's disease, Creutzfeldt-Jakob disease, Kuru. In collaboration with colleagues in Crete we have a particular interest in the (mis)folding properties of peptides that have been identified on the basis of structural studies of parts of adenovirus. We are currently using X-ray and neutron fibre diffraction methods to study the amyloid structures formed by these sequences. This work has led to a major EU funded project.

Instrumentation and Software Development

The group is involved in projects that target the development of neutron diffraction instruments as well as the software to be applied to Neutron and X-ray diffraction experiments. Dr. Sax Mason (ILL) and Prof. Forsyth, along with colleagues from ILL, Durham, and Bath universities, were instrumental in securing the funding and implementation of a completely upgraded instrument, yielding an efficiency gain of ~25 compared to the original instrument. The new diffractometer is currently being commissioned and will open up completely new areas for chemical crystallography as well as well as smaller biological systems. It will also be able to tackle a completely new range of fibre diffraction problems - both for filamentous biological systems and also synthetic polymers.

The new D19 detector, funded as part of a major EPSRC facility initiative between ILL and Durham, Keele, Bath Universities (PI Prof. JAK Howard FRS)

Other instrumentation projects include the development of algorithms to optimise absorption corrections at ESRF and ILL beamlines. This project is being carried out as part of a collaboration between ESRF, ILL, and Keele and involves a Keele-registered PhD student jointly funded by the three institutes. Ricardo Leal's work on this is now at an advanced stage (Leal et al, 2008): the basis of the approach is to generate a 3D voxel-based model of the sample using beamline sample alignment cameras, and to use this to optimise absorption corrections using very accurate path lengths through crystal, solvent and crystal mount system.

Schematic diagram illustrating sample shape reconstruction from silhouette data in 2D. In 3D a set of voxels is used in place of pixels to build up the object.	Crystal images and silhouettes of the sample determined photographically	3D model of an insulin crystal, mounted in frozen buffer and loop. Blue shows the crystal and loop components, and red the cryo-cooled buffer.
The approach has been tested on the macromolecular crystallography beamline ID23-1 at the ESRF in Grenoble using a model insulin system with the standard mini diffractometer facilities. Data from a number of crystal systems have been recorded and processed using this approach, showing significant improvement by comparison with empirical methods commonly used. This method is of general interest, particularly for long wavelength X-ray work, and for absorption effects in neutron crystallography. The approach is being further developed with a view to eventual inclusion as an option within standard data collection procedure.

Protein deuteration and exploitation for neutron scattering and NMR studies of biomolecules

Members of the Keele group were instrumental in the conception, creation, and funding of the ILL-EMBL Deuteration Laboratory. This laboratory was developed for the preparation of deuterated biological macromolecules and now operates as a thriving user facility with an active in-house programme.

The laboratory, which is run by Dr. Michael Haertlein, is geared towards the generation of a completely new line of work in the life sciences at the ILL and resulted in the generation of substantial EPSRC funding for the specific UK-driven project activity, as well EU-funded methodological developments within the NMI3 project.

Current projects include neutron structural studies of the mood stabilising drug lithium: myo-inositol monophosphatase (J. Cooper, Southampton University), structural studies of integral membrane proteins (N. Isaacs, Glasgow University), solution scattering studies of a type I restriction modification system (G. Kneale, Portsmouth University), solution studies of human pyruvate dehydrogenase (PDC) (G. Lindsay & O. Bryon, Glasgow University), deuteration methods for solid state NMR (A. Watts, Oxford), and solution studies of chromatin proteins (E. Laue, Cambridge).