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A multivariate likelihood SIRAS function for phasing and model refinement.

ABSTRACT: A likelihood function based on the multivariate probability distribution of all observed structure-factor amplitudes from a single isomorphous replacement with anomalous scattering experiment has been derived and implemented for use in substructure refinement and phasing as well as macromolecular model refinement. Efficient calculation of a multidimensional integration required for function evaluation has been achieved by approximations based on the function's properties. The use of the function in both phasing and protein model building with iterative refinement was essential for successful automated model building in the test cases presented.

SUBMITTER: Skubak P

PROVIDER: S-EPMC2748965 | biostudies-literature | 2009 Oct

REPOSITORIES: biostudies-literature

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A multivariate likelihood SIRAS function for phasing and model refinement.

Skubák Pavol P Murshudov Garib G Pannu Navraj S NS

Acta crystallographica. Section D, Biological crystallography 20090916 Pt 10

A likelihood function based on the multivariate probability distribution of all observed structure-factor amplitudes from a single isomorphous replacement with anomalous scattering experiment has been derived and implemented for use in substructure refinement and phasing as well as macromolecular model refinement. Efficient calculation of a multidimensional integration required for function evaluation has been achieved by approximations based on the function's properties. The use of the function ...[more]

PMID: 19770502

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