1 Research Complex at Harwell, Rutherford Appleton Laboratory, Oxfordshire, OX11 0FA, UK. ray@strubi.ox.ac.uk.
2 Division of Structural Biology, Henry Wellcome Building for Genomic Medicine, University of Oxford, Roosevelt Drive, Oxford, OX3 7BN, UK. ray@strubi.ox.ac.uk.
3 Structural Genomic Consortium, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford, OX3 7DQ, UK.