Rigid-body motion is the main source of diffuse scattering in protein crystallography
| Autor: | Antoine M. M. Schreurs, T. de Klijn, Loes M. J. Kroon-Batenburg |
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| Rok vydání: | 2019 |
| Předmět: |
education
010403 inorganic & nuclear chemistry 01 natural sciences Biochemistry diffuse scattering rigid-body motion 03 medical and health sciences protein crystallography General Materials Science lcsh:Science 030304 developmental biology Physics 0303 health sciences Scattering Protein dynamics General Chemistry Condensed Matter Physics Rigid body Research Papers 0104 chemical sciences Computational physics Diffuse scattering protein dynamics X-ray crystallography Supercell (crystal) lcsh:Q Protein crystallization |
| Zdroj: | IUCrJ IUCrJ, Vol 6, Iss 2, Pp 277-289 (2019) 'IUCrJ ', vol: 6, pages: 277-289 (2019) |
| ISSN: | 2052-2525 |
| DOI: | 10.1107/s2052252519000927 |
| Popis: | Diffuse scattering is caused by correlated motions in protein crystals and is a potential source of information on protein dynamics. Although internal motional models were able to reproduce the diffuse scattering to a limited extent in earlier research, it is shown here that by far the most dominant contribution is from rigid-body translations, with internal motions contributing only a small part to the total scattering. Possibilities for extracting information on internal motions, despite these findings, are discussed. The origin of diffuse X-ray scattering from protein crystals has been the subject of debate over the past three decades regarding whether it arises from correlated atomic motions within the molecule or from rigid-body disorder. Here, a supercell approach to modelling diffuse scattering is presented that uses ensembles of molecular models representing rigid-body motions as well as internal motions as obtained from ensemble refinement. This approach allows oversampling of Miller indices and comparison with equally oversampled diffuse data, thus allowing the maximum information to be extracted from experiments. It is found that most of the diffuse scattering comes from correlated motions within the unit cell, with only a minor contribution from longer-range correlated displacements. Rigid-body motions, and in particular rigid-body translations, make by far the most dominant contribution to the diffuse scattering, and internal motions give only a modest addition. This suggests that modelling biologically relevant protein dynamics from diffuse scattering may present an even larger challenge than was thought. |
| Databáze: | OpenAIRE |
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