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1d56
From Proteopedia
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|PDB= 1d56 |SIZE=350|CAPTION= <scene name='initialview01'>1d56</scene>, resolution 1.700Å | |PDB= 1d56 |SIZE=350|CAPTION= <scene name='initialview01'>1d56</scene>, resolution 1.700Å | ||
|SITE= | |SITE= | ||
| - | |LIGAND= <scene name='pdbligand=CA:CALCIUM ION'>CA</scene> | + | |LIGAND= <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <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=1d56 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1d56 OCA], [http://www.ebi.ac.uk/pdbsum/1d56 PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1d56 RCSB]</span> | ||
}} | }} | ||
| Line 24: | Line 27: | ||
[[Category: Quintana, J.]] | [[Category: Quintana, J.]] | ||
[[Category: Yuan, H.]] | [[Category: Yuan, H.]] | ||
| - | [[Category: CA]] | ||
[[Category: b-dna]] | [[Category: b-dna]] | ||
[[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 Sun Mar 30 19:34:52 2008'' |
Revision as of 16:34, 30 March 2008
| |||||||
| , resolution 1.700Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | , , , , | ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
ALTERNATIVE STRUCTURES FOR ALTERNATING POLY(DA-DT) TRACTS: THE STRUCTURE OF THE B-DNA DECAMER C-G-A-T-A-T-A-T-C-G
Overview
The X-ray crystal structure of the decamer C-G-A-T-A-T-A-T-C-G has been solved with two contrasting cations, Ca2+ and Mg2+. Crystals with calcium are space group P2(1)2(1)2(1), cell dimensions a = 38.76 A, b = 40.06 A, and c = 33.73 A, and diffract to 1.7-A resolution. Crystals with magnesium have the same space group, cell dimensions a = 38.69 A, b = 39.56 A, and c = 33.64 A, and diffract to 2.0 A. Their structures were solved independently by molecular replacement, beginning with idealized Arnott B-DNA geometry. The calcium structure refined to R = 17.8% for the 3683 reflections greater than 2 sigma, with 404 DNA atoms, 95 solvent peaks, and 1 Ca(H2O)7(2+) ion. The magnesium structure refined to R = 16.5% for the 1852 reflections greater than 2 sigma, with 404 DNA atoms, 62 solvent peaks, and 1 Mg(H2O)6(2+) ion. The two structures are virtually identical and are isostructural with C-G-A-T-C-G-A-T-C-G [Grzeskowiak et al. (1991) J. Biol. Chem. 266, 8861-8883] and C-G-A-T-T-A-A-T-C-G [Quintana et al. (1992) J. Mol. Biol. 225, 375-395]. Comparison of C-G-A-T-A-T-A-T-C-G with C-G-C-A-T-A-T-A-T-G-C-G [Yoon et al. (1988) Proc. Natl. Acad. Sci. U.S.A. 85, 6332-6336] shows that the expected alternation of twist angles is found in the central A-T-A-T-A-T region of the decamer (A-T small, T-A large), but the minor groove remains wide at the center, rather than narrow. Minor groove narrowing is produced, in these two structures, not by overwinding of the helix, but by an increase in base pair propeller. This analysis confirms the concept that poly(dA-dT).poly(dA-dT) is polymorphous, with different local conformations possible in different local environments.
About this Structure
1D56 is a Protein complex structure of sequences from [1]. Full crystallographic information is available from OCA.
Reference
Alternative structures for alternating poly(dA-dT) tracts: the structure of the B-DNA decamer C-G-A-T-A-T-A-T-C-G., Yuan H, Quintana J, Dickerson RE, Biochemistry. 1992 Sep 1;31(34):8009-21. PMID:1510987
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