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2a5m
From Proteopedia
NMR structure of murine gamma-S crystallin from joint refinement with SAXS data
Overview
Determination of the 3D structures of multidomain proteins by solution NMR methods presents a number of unique challenges related to their larger molecular size and the usual scarcity of constraints at the interdomain interface, often resulting in a decrease in structural accuracy. In this respect, experimental information from small-angle scattering of X-ray radiation in solution (SAXS) presents a suitable complement to the NMR data, as it provides an independent constraint on the overall molecular shape. A computational procedure is described that allows incorporation of such SAXS data into the mainstream high-resolution macromolecular structure refinement. The method is illustrated for a two-domain 177-amino-acid protein, gammaS crystallin, using an experimental SAXS data set fitted at resolutions from approximately 200 A to approximately 30 A. Inclusion of these data during structure refinement decreases the backbone coordinate root-mean-square difference between the derived model and the high-resolution crystal structure of a 54% homologous gammaB crystallin from 1.96 +/- 0.07 A to 1.31 +/- 0.04 A. Combining SAXS data with NMR restraints can be accomplished at a moderate computational expense and is expected to become useful for multidomain proteins, multimeric assemblies, and tight macromolecular complexes.
About this Structure
2A5M is a Single protein structure of sequence from Mus musculus. Full crystallographic information is available from OCA.
Reference
Refinement of multidomain protein structures by combination of solution small-angle X-ray scattering and NMR data., Grishaev A, Wu J, Trewhella J, Bax A, J Am Chem Soc. 2005 Nov 30;127(47):16621-8. PMID:16305251 Page seeded by OCA on Sat May 3 18:38:22 2008
