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Macromolecular X-ray structure determination using weak, single-wavelength anomalous data.

ABSTRACT: We describe a likelihood-based method for determining the substructure of anomalously scattering atoms in macromolecular crystals that allows successful structure determination by single-wavelength anomalous diffraction (SAD) X-ray analysis with weak anomalous signal. With the use of partial models and electron density maps in searches for anomalously scattering atoms, testing of alternative values of parameters and parallelized automated model-building, this method has the potential to extend the applicability of the SAD method in challenging cases.

SUBMITTER: Bunkoczi G

PROVIDER: S-EPMC4312553 | biostudies-literature | 2015 Feb

REPOSITORIES: biostudies-literature

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Macromolecular X-ray structure determination using weak, single-wavelength anomalous data.

Bunkóczi Gábor G McCoy Airlie J AJ Echols Nathaniel N Grosse-Kunstleve Ralf W RW Adams Paul D PD Holton James M JM Read Randy J RJ Terwilliger Thomas C TC

Nature methods 20141222 2

We describe a likelihood-based method for determining the substructure of anomalously scattering atoms in macromolecular crystals that allows successful structure determination by single-wavelength anomalous diffraction (SAD) X-ray analysis with weak anomalous signal. With the use of partial models and electron density maps in searches for anomalously scattering atoms, testing of alternative values of parameters and parallelized automated model-building, this method has the potential to extend t ...[more]

PMID: 25532136

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