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4bna
From Proteopedia
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| , resolution 2.300Å | |||||||
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| Ligands: | , , , , | ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
REVERSIBLE BENDING AND HELIX GEOMETRY IN A B-DNA DODECAMER: CGCGAATTBRCGCG
Overview
A double-helical B-DNA dodecamer has been analyzed by single crystal x-ray diffraction methods and refined independently in four variants: sequence CGCGAATTCGCG at 20 degrees C and at 16 K, and CGCGAATTBrCGCG in 60% methylpentanediol at 20 and at 7 degrees C. The first three forms show a 14-19 degrees bend in overall helix axis, but the fourth is straight and unbent. Detailed comparisons of the various forms have led to a better understanding of helix geometry and bending. Structural principles can be understood best if organized under four headings: 1) intrinsic geometry of the sugar rings, 2) stacking and relative motion of base pairs, 3) geometry of the connecting phosphate backbone, and 4) mechanics of bending in B-DNA. The observed bending is neither completely localized nor smooth and continuous, but an intermediate compromise that can be termed "annealed kinking."
About this Structure
4BNA is a Protein complex structure of sequences from [1]. Full crystallographic information is available from OCA.
Reference
Reversible bending and helix geometry in a B-DNA dodecamer: CGCGAATTBrCGCG., Fratini AV, Kopka ML, Drew HR, Dickerson RE, J Biol Chem. 1982 Dec 25;257(24):14686-707. PMID:7174662
Page seeded by OCA on Mon Mar 31 05:38:05 2008
