161d
From Proteopedia
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| - | + | {{STRUCTURE_161d| PDB=161d | SCENE= }} | |
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'''A SINGLE 2'-HYDROXYL GROUP CONVERTS B-DNA TO A-DNA: CRYSTAL STRUCTURE OF THE DNA-RNA CHIMERIC DECAMER DUPLEX D(CCGGC)R(G)D(CCGG) WITH A NOVEL INTERMOLECULAR G.C BASE-PAIRED QUADRUPLET''' | '''A SINGLE 2'-HYDROXYL GROUP CONVERTS B-DNA TO A-DNA: CRYSTAL STRUCTURE OF THE DNA-RNA CHIMERIC DECAMER DUPLEX D(CCGGC)R(G)D(CCGG) WITH A NOVEL INTERMOLECULAR G.C BASE-PAIRED QUADRUPLET''' | ||
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==About this Structure== | ==About this Structure== | ||
| - | + | Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=161D OCA]. | |
==Reference== | ==Reference== | ||
A single 2'-hydroxyl group converts B-DNA to A-DNA. Crystal structure of the DNA-RNA chimeric decamer duplex d(CCGGC)r(G)d(CCGG) with a novel intermolecular G-C base-paired quadruplet., Ban C, Ramakrishnan B, Sundaralingam M, J Mol Biol. 1994 Feb 11;236(1):275-85. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/7508984 7508984] | A single 2'-hydroxyl group converts B-DNA to A-DNA. Crystal structure of the DNA-RNA chimeric decamer duplex d(CCGGC)r(G)d(CCGG) with a novel intermolecular G-C base-paired quadruplet., Ban C, Ramakrishnan B, Sundaralingam M, J Mol Biol. 1994 Feb 11;236(1):275-85. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/7508984 7508984] | ||
| - | [[Category: Protein complex]] | ||
[[Category: Ban, C.]] | [[Category: Ban, C.]] | ||
[[Category: Ramakrishnan, B.]] | [[Category: Ramakrishnan, B.]] | ||
[[Category: Sundaralingam, M.]] | [[Category: Sundaralingam, M.]] | ||
| - | [[Category: | + | [[Category: A-dna/rna]] |
| - | [[Category: | + | [[Category: Double helix]] |
| - | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri May 2 09:31:53 2008'' | |
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | |
Revision as of 06:31, 2 May 2008
A SINGLE 2'-HYDROXYL GROUP CONVERTS B-DNA TO A-DNA: CRYSTAL STRUCTURE OF THE DNA-RNA CHIMERIC DECAMER DUPLEX D(CCGGC)R(G)D(CCGG) WITH A NOVEL INTERMOLECULAR G.C BASE-PAIRED QUADRUPLET
Overview
We have found that the introduction of a single 2'-hydroxyl group on the sugar-phosphate backbone of the B-DNA decamer d(CCGGCGCCGG) transforms it to A-DNA. Thus, for the first time the X-ray structures of the same sequence have been observed in both the A and B-DNA conformations, permitting a comparison. Crystals of the DNA-RNA chimeric decamer d(CCGGC)r(G)d(CCGG) belong to the orthorhombic space group P2(1)2(1)2(1) with unit cell dimensions a = 25.63 A, b = 45.24 A and c = 47.99 A, and one decamer duplex in the asymmetric unit. The structure was solved by a rigid body search using the coordinates of the isomorphous structure d(CCCGGCCGGG) and refined to an R value of 0.136 using 2753 unique reflections at 1.9 A resolution. The final model contains 406 nucleotide atoms and 61 water molecules. The chimeric duplex exhibits typical A-DNA geometry, with all the sugars in the C(3')-endo puckering and the base-pairs inclined and displaced from the helix axis. The 2'-hydroxyl groups on rG6 and rG16 protrude into the minor groove surface and form different types of hydrogen bonds; that on strand 1 forms an intermolecular hydrogen bond with the furanose ring O(4') of a symmetry-related C1 residue, while that on strand 2 is involved in two water bridges. Crystal packing forces the G4-G17 base-pair in the top half of the duplex to slide significantly into the minor groove compared to the corresponding G7-G14 base-pair in the bottom half, resulting in these base-pairs exhibiting different base stacking and intermolecular interactions. The base G4 of the G4-G17 base-pair forms an unorthodox base "triple", G4*(G10-C11), hydrogen-bonding through its minor groove sites N(2) and N(3) to the minor groove atoms N(2) and O(2) of both bases of the G10-C11 base-pair of a symmetry-related molecule. The base G10 of this triple in turn forms a second similar unorthodox base triple, G10*(G3*C18), with the adjacent base-pair G3-C18 of the duplex, thus G10 is involved in a double triple. On the other hand, in the bottom half of the duplex, the C7-G14 base-pair is involved only in a single similar unorthodox base triple with G20, (C7-G14)*G20, while the adjacent base-pair rG6-C15 is involved in a novel quadruple with C1-G20, (rG6-C15) *(C1-G20), where the latter base-pairs are hydrogen-bonded to each other via the minor groove sites G(N(2))...C(O(2)).(ABSTRACT TRUNCATED AT 400 WORDS)
About this Structure
Full crystallographic information is available from OCA.
Reference
A single 2'-hydroxyl group converts B-DNA to A-DNA. Crystal structure of the DNA-RNA chimeric decamer duplex d(CCGGC)r(G)d(CCGG) with a novel intermolecular G-C base-paired quadruplet., Ban C, Ramakrishnan B, Sundaralingam M, J Mol Biol. 1994 Feb 11;236(1):275-85. PMID:7508984 Page seeded by OCA on Fri May 2 09:31:53 2008
