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Rapid model building of alpha-helices in electron-density maps.

ABSTRACT: A method for the identification of alpha-helices in electron-density maps at low resolution followed by interpretation at moderate to high resolution is presented. Rapid identification is achieved at low resolution, where alpha-helices appear as tubes of density. The positioning and direction of the alpha-helices is obtained at moderate to high resolution, where the positions of side chains can be seen. The method was tested on a set of 42 experimental electron-density maps at resolutions ranging from 1.5 to 3.8 A. An average of 63% of the alpha-helical residues in these proteins were built and an average of 76% of the residues built matched helical residues in the refined models of the proteins. The overall average r.m.s.d. between main-chain atoms in the modeled alpha-helices and the nearest atom with the same name in the refined models of the proteins was 1.3 A.

SUBMITTER: Terwilliger TC

PROVIDER: S-EPMC2827347 | biostudies-literature | 2010 Mar

REPOSITORIES: biostudies-literature

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Rapid model building of alpha-helices in electron-density maps.

Terwilliger Thomas C TC

Acta crystallographica. Section D, Biological crystallography 20100212 Pt 3

A method for the identification of alpha-helices in electron-density maps at low resolution followed by interpretation at moderate to high resolution is presented. Rapid identification is achieved at low resolution, where alpha-helices appear as tubes of density. The positioning and direction of the alpha-helices is obtained at moderate to high resolution, where the positions of side chains can be seen. The method was tested on a set of 42 experimental electron-density maps at resolutions rangin ...[more]

PMID: 20179338

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