X-ray crystallography and NMR can provide detailed structural information of protein-protein complexes, but technical problems make their application challenging in the high-throughput regime. Other methods such as small-angle X-ray scattering (SAXS) are more promising for large-scale application, but at the cost of lower resolution, which is a problem that can be solved by complementing SAXS data with theoretical simulations. Here, we propose a novel strategy that combines SAXS data and accurate protein-protein docking simulations. The approach has been benchmarked on a large pool of known structures with synthetic SAXS data, and on three experimental examples. The combined approach (pyDockSAXS) provided a significantly better success rate (43% for the top 10 predictions) than either of the two methods alone. Further analysis of the influence of different docking parameters made it possible to increase the success rates for specific cases, and to define guidelines for improving the data-driven protein-protein docking protocols.
Bibliographical noteFunding Information:
We acknowledge financial support from the MICINN ( BIO2008-02882 , BIO2009-10964 , Consolider E-Science; Combiomed ISCIII), the Spanish Ministry of Education-FEDER ( BIO2007-63458 ) and the Fundación Marcelino Botín. P.B. holds a Ramón y Cajal contract funded, in part, by the Spanish Ministry of Education. D.S. acknowledges financial support from the HFSP Research Grant RGP 55/2006 and thanks Dr W-D. Schubert for the permission to use the internalin/cadherin data.
- Binding energy
- Protein complex structure
- Protein-protein interactions
- Small-angle X-ray scattering