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3ana
From Proteopedia
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THREE-DIMENSIONAL STRUCTURE OF D(GGGATCCC) IN THE CRYSTALLINE STATE
Overview
The structure of the self-complementary octamer d(GGGATCCC) has been, analysed by single crystal X-ray diffraction methods at a nominal, resolution of 2.5 A. With acceptable stereochemistry of the model the, crystallographic R factor was 16.6% after restrained least-squares, refinement. In the crystal, d(GGGATCCC) forms an A-DNA double helix with, slightly varying conformation of the two strands. The average displacement, of the base pairs from the helix axis is unusually large and is, accompanied by pronounced sliding of the base pairs along their long axes, at all dinucleotide steps except for the central AT. With 12 base pairs, per complete turn the helix is considerably underwound. As observed with, most oligodeoxyribonucleotides analysed by X-ray crystallography so far, the octamer displays reduced base pair tilt, increased rise per base pair, and a more open major groove compared with canonical A-DNA. We propose, that, based on these parameters, three A-helical sub-families may be, defined; d(GGGATCCC) then is a representative of the class with, intermediate tilt, rise, and major groove width.
About this Structure
3ANA is a Protein complex structure of sequences from [1]. Full crystallographic information is available from OCA.
Reference
Three-dimensional structure of d(GGGATCCC) in the crystalline state., Lauble H, Frank R, Blocker H, Heinemann U, Nucleic Acids Res. 1988 Aug 25;16(16):7799-816. PMID:3166518
Page seeded by OCA on Tue Jan 29 21:38:10 2008
