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| - | [[Image:1d88.gif|left|200px]] | |
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| - | {{Structure
| + | ==CONFORMATIONAL INFLUENCE OF THE RIBOSE 2'-HYDROXYL GROUP: CRYSTAL STRUCTURES OF DNA-RNA CHIMERIC DUPLEXES== |
| - | |PDB= 1d88 |SIZE=350|CAPTION= <scene name='initialview01'>1d88</scene>, resolution 2.000Å
| + | <StructureSection load='1d88' size='340' side='right'caption='[[1d88]], [[Resolution|resolution]] 2.00Å' scene=''> |
| - | |SITE=
| + | == Structural highlights == |
| - | |LIGAND=
| + | <table><tr><td colspan='2'>[[1d88]] is a 2 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1D88 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1D88 FirstGlance]. <br> |
| - | |ACTIVITY=
| + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2Å</td></tr> |
| - | |GENE=
| + | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=1d88 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1d88 OCA], [https://pdbe.org/1d88 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1d88 RCSB], [https://www.ebi.ac.uk/pdbsum/1d88 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1d88 ProSAT]</span></td></tr> |
| - | }}
| + | </table> |
| - | | + | __TOC__ |
| - | '''CONFORMATIONAL INFLUENCE OF THE RIBOSE 2'-HYDROXYL GROUP: CRYSTAL STRUCTURES OF DNA-RNA CHIMERIC DUPLEXES'''
| + | </StructureSection> |
| - | | + | [[Category: Large Structures]] |
| - | | + | [[Category: Egli M]] |
| - | ==Overview== | + | [[Category: Rich A]] |
| - | We have crystallized three double-helical DNA-RNA chimeric duplexes and determined their structures by X-ray crystallography at resolutions between 2 and 2.25 A. The two self-complementary duplexes [r(G)d(CGTATACGC)]2 and [d(GCGT)r(A)d(TACGC)]2, as well as the Okazaki fragment d(GGGTATACGC).r(GCG)d(TATACCC), were found to adopt A-type conformations. The crystal structures are non-isomorphous, and the crystallographic environments for the three chimeras are different. A number of intramolecular interactions of the ribose 2'-hydroxyl groups contribute to the stabilization of the A-conformation. Hydrogen bonds between 2'-hydroxyls and 5'-oxygens or phosphate oxygens, in addition to the previously observed hydrogen bonds to 1'-oxygens of adjacent riboses and deoxyriboses, are observed in the DNA-RNA chimeric duplexes. The crystalline chimeric duplexes do not show a transition between the DNA A- and B-conformations. CD spectra suggest that the Okazaki fragment assumes an A-conformation in solution as well. In this molecule the three RNA residues may therefore lock the complete decamer in the A-conformation. Crystals of an all-DNA strand with the same sequence as the self-complementary chimeras show a morphology which is different from those of the chimera crystals. Moreover, the oligonucleotide does not match any of the sequence characteristics of DNAs usually adopting the A-conformation in the crystalline state (e.g., octamers with short alternating stretches of purines and pyrimidines). In DNA-RNA chimeric duplexes, it is therefore possible that a single RNA residue can drive the conformational equilibrium toward the A-conformation.
| + | [[Category: Usman N]] |
| - | | + | |
| - | ==About this Structure== | + | |
| - | 1D88 is a [[Protein complex]] structure of sequences from [http://en.wikipedia.org/wiki/ ]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1D88 OCA].
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| - | ==Reference==
| + | |
| - | Conformational influence of the ribose 2'-hydroxyl group: crystal structures of DNA-RNA chimeric duplexes., Egli M, Usman N, Rich A, Biochemistry. 1993 Apr 6;32(13):3221-37. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/7681688 7681688]
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| - | [[Category: Protein complex]] | + | |
| - | [[Category: Egli, M.]] | + | |
| - | [[Category: Rich, A.]] | + | |
| - | [[Category: Usman, N.]] | + | |
| - | [[Category: a-dna/rna]]
| + | |
| - | [[Category: double helix]]
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| - | | + | |
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 10:34:26 2008''
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