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Finding non-crystallographic symmetry in density maps of macromolecular structures.

ABSTRACT: The internal symmetry of a macromolecule is both an important aspect of its function and a useful feature in obtaining a structure by X-ray crystallography and other techniques. A method is presented for finding internal symmetry and other non-crystallographic symmetry in a structure based on patterns of density in a density map for that structure. Regions in map that are similar are identified by cutting out a sphere of density from a region that has high local variation and using an FFT-based correlation search to find other regions that match. The relationships among correlated regions are then refined to maximize their correlations and are found to accurately represent non-crystallographic symmetry in the map.

SUBMITTER: Terwilliger TC

PROVIDER: S-EPMC3757268 | biostudies-literature | 2013 Sep

REPOSITORIES: biostudies-literature

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Finding non-crystallographic symmetry in density maps of macromolecular structures.

Terwilliger Thomas C TC

Journal of structural and functional genomics 20130724 3

The internal symmetry of a macromolecule is both an important aspect of its function and a useful feature in obtaining a structure by X-ray crystallography and other techniques. A method is presented for finding internal symmetry and other non-crystallographic symmetry in a structure based on patterns of density in a density map for that structure. Regions in map that are similar are identified by cutting out a sphere of density from a region that has high local variation and using an FFT-based ...[more]

PMID: 23881095

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