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Multi-crystal native SAD analysis at 6?keV.

ABSTRACT: Anomalous diffraction signals from typical native macromolecules are very weak, frustrating their use in de novo structure determination. Here, native SAD procedures are described to enhance signal to noise in anomalous diffraction by using multiple crystals in combination with synchrotron X-rays at 6?keV. Increased anomalous signals were obtained at 6?keV compared with 7?keV X-ray energy, which was used for previous native SAD analyses. A feasibility test of multi-crystal-based native SAD phasing was performed at 3.2?Å resolution for a known tyrosine protein kinase domain, and real-life applications were made to two novel membrane proteins at about 3.0?Å resolution. The three applications collectively serve to validate the robust feasibility of native SAD phasing at lower energy.

SUBMITTER: Liu Q

PROVIDER: S-EPMC4188002 | biostudies-literature | 2014 Oct

REPOSITORIES: biostudies-literature

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Multi-crystal native SAD analysis at 6 keV.

Liu Qun Q Guo Youzhong Y Chang Yanqi Y Cai Zheng Z Assur Zahra Z Mancia Filippo F Greene Mark I MI Hendrickson Wayne A WA

Acta crystallographica. Section D, Biological crystallography 20140930 Pt 10

Anomalous diffraction signals from typical native macromolecules are very weak, frustrating their use in de novo structure determination. Here, native SAD procedures are described to enhance signal to noise in anomalous diffraction by using multiple crystals in combination with synchrotron X-rays at 6 keV. Increased anomalous signals were obtained at 6 keV compared with 7 keV X-ray energy, which was used for previous native SAD analyses. A feasibility test of multi-crystal-based native SAD phasi ...[more]

PMID: 25286840

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