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High regularity of Z-DNA revealed by ultra high-resolution crystal structure at 0.55 A.

ABSTRACT: The crystal structure of a Z-DNA hexamer duplex d(CGCGCG)(2) determined at ultra high resolution of 0.55 Å and refined without restraints, displays a high degree of regularity and rigidity in its stereochemistry, in contrast to the more flexible B-DNA duplexes. The estimations of standard uncertainties of all individually refined parameters, obtained by full-matrix least-squares optimization, are comparable with values that are typical for small-molecule crystallography. The Z-DNA model generated with ultra high-resolution diffraction data can be used to revise the stereochemical restraints applied in lower resolution refinements. Detailed comparisons of the stereochemical library values with the present accurate Z-DNA parameters, shows in general a good agreement, but also reveals significant discrepancies in the description of guanine-sugar valence angles and in the geometry of the phosphate groups.

SUBMITTER: Brzezinski K

PROVIDER: S-EPMC3152349 | biostudies-literature | 2011 Aug

REPOSITORIES: biostudies-literature

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High regularity of Z-DNA revealed by ultra high-resolution crystal structure at 0.55 A.

Brzezinski Krzysztof K Brzuszkiewicz Anna A Dauter Miroslawa M Kubicki Maciej M Jaskolski Mariusz M Dauter Zbigniew Z

Nucleic acids research 20110401 14

The crystal structure of a Z-DNA hexamer duplex d(CGCGCG)(2) determined at ultra high resolution of 0.55 Å and refined without restraints, displays a high degree of regularity and rigidity in its stereochemistry, in contrast to the more flexible B-DNA duplexes. The estimations of standard uncertainties of all individually refined parameters, obtained by full-matrix least-squares optimization, are comparable with values that are typical for small-molecule crystallography. The Z-DNA model generate ...[more]

PMID: 21459852

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