RESEARCH
James currently works on Type I bacterial restriction-modification systems. He uses a wide range of molecular biology techniques for the cloning and purification of proteins for analysis by biophysical techniques such as EMSAs, light scattering, analytical ultracentrifugation (sedimentation equilibrium and sedimentation velocity) and small-angle neutron scattering, the latter requiring visits to the D22 beamline at the internationally recognised, Institut Laue-Langevin (ILL) in Grenoble, France.
Our aim is to investigate the structure, activity, subunit interactions, and DNA-induced conformational changes of the endonuclease and methyltransferase complexes. Recently, we have been developing small angle neutron scattering techniques, making use of contrast variation and selective deuteration. EcoR124INT provides a tractable system for such studies. Each of the three subunits can now be prepared in soluble form, such that they can be separately deuterated. Additionally, we will analyse the interaction of the MTase and ENase with ocr, a small inhibitor protein that mimics DNA and blocks the DNA binding site of Type I enzymes.