Bulk-solvent correction in large macromolecular structures.

Bernard Rees; Lasse Jenner; Marat Yusupov

doi:10.1107/s0907444905019591

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PubMed · 16131764

Bulk-solvent correction in large macromolecular structures.

Bernard Rees·Lasse Jenner·Marat Yusupov

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Abstract

The estimation of the bulk-solvent contribution to the diffraction of a macromolecular crystal makes use of a solvent mask which delimits the bulk-solvent regions in the crystal. It is shown that the way this mask is usually defined in CNS contains a bias which can lead to absurd results in the case of very large structures, where the calculations can only be made on relatively coarse grids. A modified procedure is described and applied to 70S ribosome data at 5.5 A resolution. The B factor affecting the bulk solvent is also discussed. Even in this case of very high and widely variable atomic B factors, it seems sufficient to consider a constant and isotropic B factor for the bulk solvent. This is initially set to the average value of the atomic B factor, but can be refined.

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Macromolecular Substances Ribosomes Solvents Thermus thermophilus X-Ray Diffraction Journal Article

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BibTeX RIS

Bernard Rees, Lasse Jenner, Marat Yusupov. 2005-08-16. Bulk-solvent correction in large macromolecular structures.. https://doi.org/10.1107/s0907444905019591

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