|
|
| (14 intermediate revisions by the same user not shown) |
| Line 1: |
Line 1: |
| [[Image:1d75.gif|left|200px]]<br /><applet load="1d75" size="450" color="white" frame="true" align="right" spinBox="true"
| |
| caption="1d75, resolution 2.800Å" />
| |
| '''CONFORMATION OF THE GUANINE.8-OXOADENINE BASE PAIRS IN THE CRYSTAL STRUCTURE OF D(CGCGAATT(O8A)GCG)'''<br />
| |
|
| |
|
| ==Overview== | | ==CONFORMATION OF THE GUANINE.8-OXOADENINE BASE PAIRS IN THE CRYSTAL STRUCTURE OF D(CGCGAATT(O8A)GCG)== |
| The structure of the synthetic deoxydodecamer d(CGCGAATT(O8A)GCG)2 (O8A =, 8-oxoadenine) has been determined by single-crystal X-ray diffraction, techniques. The oligonucleotide crystallizes in the orthorhombic space, group P2(1)2(1)2(1) with cell dimensions of a = 25.48 A, b = 41.84 A, and, c = 64.91 A. The refinement has converged with an R-factor of 0.151 for, 1119 reflections in the resolution range 8.0-2.25 A. Sixty-seven solvent, molecules were located during the course of the refinement. The B-DNA, helix consists of ten Watson-Crick base pairs and two guanine-8-oxoadenine, (G.O8A) base pairs. In order to achieve hydrogen-bonding complementarity, between the two bases, an unusual G(anti).O8A-(syn) wobble conformation is, adopted. It is proposed that the G.O8A mispairs are held together by a, network of four interbase hydrogen bonds which are the result of the, formation of two reverse three-center hydrogen-bonding systems. These, involve one carbonyl oxygen lone pair interacting with two hydrogen atoms., In a departure from previous observations of the characteristics of, purine-purine anti-syn base pairs, lambda 1 and lambda 2, the angles, between the glycosidic bonds and the C1'-C1' vector, are symmetric. A, reassessment of the other purine-purine mispairs suggests that similar, three-center hydrogen bonds may occur and make a contribution to, stabilizing other base pairings.
| | <StructureSection load='1d75' size='340' side='right'caption='[[1d75]], [[Resolution|resolution]] 2.80Å' scene=''> |
| | | == Structural highlights == |
| ==About this Structure== | | <table><tr><td colspan='2'>[[1d75]] is a 2 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1D75 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1D75 FirstGlance]. <br> |
| 1D75 is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/ ]. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1D75 OCA].
| | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.8Å</td></tr> |
| | | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=A38:8-OXY+DEOXYADENOSINE-5-MONOPHOSPHATE'>A38</scene></td></tr> |
| ==Reference== | | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=1d75 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1d75 OCA], [https://pdbe.org/1d75 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1d75 RCSB], [https://www.ebi.ac.uk/pdbsum/1d75 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1d75 ProSAT]</span></td></tr> |
| Conformation of guanine-8-oxoadenine base pairs in the crystal structure of d(CGCGAATT(O8A)GCG)., Leonard GA, Guy A, Brown T, Teoule R, Hunter WN, Biochemistry. 1992 Sep 15;31(36):8415-20. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=1390625 1390625]
| | </table> |
| [[Category: Protein complex]] | | __TOC__ |
| [[Category: Brown, T.]]
| | </StructureSection> |
| [[Category: Guy, A.]]
| | [[Category: Large Structures]] |
| [[Category: Hunter, W.N.]] | | [[Category: Brown T]] |
| [[Category: Leonard, G.A.]] | | [[Category: Guy A]] |
| [[Category: Teoule, R.]] | | [[Category: Hunter WN]] |
| [[Category: b-dna]] | | [[Category: Leonard GA]] |
| [[Category: double helix]] | | [[Category: Teoule R]] |
| [[Category: mismatched]] | |
| [[Category: modified]] | |
| | |
| ''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Sun Nov 25 02:38:24 2007''
| |
