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CrystTwiV: a webserver for automated phase extension and refinement in X-ray crystallography.

ABSTRACT: An important stage in macromolecular crystallography is that of phase extension and refinement when initial phase estimates are available from isomorphous replacement or anomalous scattering or other methods. For this purpose, an alternative method called the twin variables (TwiV) method has been proposed. The algorithm is based on alternately transferring the phase information between the twin variable sets. The phase extension and refinement is evaluated with the crystallographic symmetry test by deliberately sacrificing the space-group symmetry in the starting set, then using its re-appearance as a criterion for correctness. Here we present a software program (CrysTwiV) that runs on the web (freely available at: http://btweb.aua.gr/crystwiv/) implementing the above-mentioned method.

SUBMITTER: Thireou T

PROVIDER: S-EPMC1933117 | biostudies-literature | 2007 Jul

REPOSITORIES: biostudies-literature

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CrystTwiV: a webserver for automated phase extension and refinement in X-ray crystallography.

Thireou Trias T Atlamazoglou Vassilis V Levakis Manolis M Eliopoulos Elias E Hountas Athanassios A Tsoucaris George G Bethanis Kostas K

Nucleic acids research 20070508 Web Server issue

An important stage in macromolecular crystallography is that of phase extension and refinement when initial phase estimates are available from isomorphous replacement or anomalous scattering or other methods. For this purpose, an alternative method called the twin variables (TwiV) method has been proposed. The algorithm is based on alternately transferring the phase information between the twin variable sets. The phase extension and refinement is evaluated with the crystallographic symmetry test ...[more]

PMID: 17488848

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