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3bna
From Proteopedia
(New page: 200px<br /><applet load="3bna" size="350" color="white" frame="true" align="right" spinBox="true" caption="3bna, resolution 3.000Å" /> '''REVERSIBLE BENDING ...) |
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==Overview== | ==Overview== | ||
| - | A double-helical B-DNA dodecamer has been analyzed by single crystal x-ray | + | 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== | ==About this Structure== | ||
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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:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=7174662 7174662] | 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:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=7174662 7174662] | ||
[[Category: Protein complex]] | [[Category: Protein complex]] | ||
| - | [[Category: Dickerson, R | + | [[Category: Dickerson, R E.]] |
| - | [[Category: Fratini, A | + | [[Category: Fratini, A V.]] |
| - | [[Category: Kopka, M | + | [[Category: Kopka, M L.]] |
[[Category: b-dna]] | [[Category: b-dna]] | ||
[[Category: double helix]] | [[Category: double helix]] | ||
[[Category: modified]] | [[Category: modified]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 19:06:38 2008'' |
Revision as of 17:06, 21 February 2008
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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
3BNA 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 Thu Feb 21 19:06:38 2008
