Combining NMR docking data with EPR distances and in silico calculations for a more complete model of colicin protein-protein interactions

<p>Currently atomic resolution structures of protein-protein interactions are commonly limited to X-ray crystallography or NMR, developments in these fields have allowed for more accurate and biologically relevant structures to be developed  however ab initio information still remains a developing field.</p> <p>Site-directed spin labelling (SDSL) in combination with electron paramagnetic resonance (EPR) pulsed electron double resonance (PELDOR) allows for the precise measurement of intra and intermolecular distances. New in silico methods allow for comparison to the experimental. SDSL at several sites within a complex allows a three dimensional model tobe built up using distance constraints, which when combined with NMR docking data gives a comprehensive model.</p> <p>Using the well-characterised system, of colicin E9 and its cognate inhibitor, Im9 a comprehensive solution is being developed to combine such NMR docking models, with PELDOR distance (and angle) constraints and in silico computations which are comparable to X-ray crystallographic models.</p> <p> </p>