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287d
From Proteopedia
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|PDB= 287d |SIZE=350|CAPTION= <scene name='initialview01'>287d</scene>, resolution 2.200Å | |PDB= 287d |SIZE=350|CAPTION= <scene name='initialview01'>287d</scene>, resolution 2.200Å | ||
|SITE= | |SITE= | ||
| - | |LIGAND= | + | |LIGAND= <scene name='pdbligand=DA:2'-DEOXYADENOSINE-5'-MONOPHOSPHATE'>DA</scene>, <scene name='pdbligand=DC:2'-DEOXYCYTIDINE-5'-MONOPHOSPHATE'>DC</scene>, <scene name='pdbligand=DG:2'-DEOXYGUANOSINE-5'-MONOPHOSPHATE'>DG</scene>, <scene name='pdbligand=DT:THYMIDINE-5'-MONOPHOSPHATE'>DT</scene> |
|ACTIVITY= | |ACTIVITY= | ||
|GENE= | |GENE= | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY= | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=287d FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=287d OCA], [http://www.ebi.ac.uk/pdbsum/287d PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=287d RCSB]</span> | ||
}} | }} | ||
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[[Category: double helix]] | [[Category: double helix]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Mar 31 01:45:54 2008'' |
Revision as of 22:45, 30 March 2008
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| , resolution 2.200Å | |||||||
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| Ligands: | , , , | ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
X-RAY AND SOLUTION STUDIES OF DNA OLIGOMERS AND IMPLICATIONS FOR THE STRUCTURAL BASIS OF A-TRACT-DEPENDENT CURVATURE
Overview
DNA containing short periodic stretches of adenine residues (known as A-tracts), which are aligned with the helical repeat, exhibit a pronounced macroscopic curvature. This property is thought to arise from the cumulative effects of a distinctive structure of the A-tract. It has also been observed by gel electrophoresis that macroscopic curvature is largely retained when inosine bases are introduced singly into A-tracts but decreases abruptly for pure I-tracts. The structural basis of this effect is unknown. Here we describe X-ray and gel electrophoretic analyses of several oligomers incorporating adenine or inosine bases or both. We find that macroscopic curvature is correlated with a distinctive base-stacking geometry characterized by propeller twisting of the base-pairs. Regions of alternating adenine and inosine bases display large propeller twisting comparable to that of pure A-tracts, whereas the values observed for pure I-tracts are significantly smaller. We also observe in the crystal structures that propeller twist leads to close cross-strand contacts between amino groups from adenine and cytosine bases, indicating an attractive NH-N interaction, which is analogous to the NH-O interaction proposed for A-tracts. This interaction also occurs between adenine bases across an A-T step and may explain in part the different behavior of A-T versus T-A steps in the context of A-tract-induced curvature. We also note that hydration patterns may contribute to propeller-twisted conformation. Based on the present data and other structural and biophysical studies, we propose that DNA macroscopic curvature is related to the structural invariance of A-tract and A-tract-like regions conferred by high propeller twist, cross-strand interactions and characteristic hydration. The implications of these findings to the mechanism of DNA bending are discussed.
About this Structure
287D is a Protein complex structure of sequences from [1]. Full crystallographic information is available from OCA.
Reference
X-ray and solution studies of DNA oligomers and implications for the structural basis of A-tract-dependent curvature., Shatzky-Schwartz M, Arbuckle ND, Eisenstein M, Rabinovich D, Bareket-Samish A, Haran TE, Luisi BF, Shakked Z, J Mol Biol. 1997 Apr 4;267(3):595-623. PMID:9126841
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