Using Small Angle Solution Scattering Data in Xplor-NIH Structure Calculations

Progress in Nuclear Magnetic Resonance Spectroscopy (Impact Factor: 7.24). 07/2014; 80. DOI: 10.1016/j.pnmrs.2014.03.001


This contribution describes the use of small and wide angle X-ray and small angle neutron scattering for biomolecular structure calculation using the program Xplor-NIH, both with and without NMR data. The current algorithms used for calculating scattering curves are described, and the use of scattering data as a structural restraint is given concrete form as a fragment of an Xplor-NIH structure calculation script. We review five examples of the use of scattering data in structure calculation, including the treatment of single domain proteins, nucleic acids, structure determination of large proteins, and the use of ensemble representations to characterize small and large amplitude motions.

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    • ". The goodness of fit to the experimental scattering curve for each of the 20 individual simulated annealing structures was also measured using the CalcSAXS helper program in the Xplor-NIH (version 2.37) software package [40] [78] and yielded values of χ 2 = 0.81 ± 0.02. e PROCHECK-NMR [90] and MolProbity [91] results include residues (A326–I655) and are of acceptable quality for an NMR structure. "
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