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| Line 8: |
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| <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=2oue FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2oue OCA], [https://pdbe.org/2oue PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2oue RCSB], [https://www.ebi.ac.uk/pdbsum/2oue PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2oue ProSAT]</span></td></tr> | | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=2oue FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2oue OCA], [https://pdbe.org/2oue PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2oue RCSB], [https://www.ebi.ac.uk/pdbsum/2oue PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2oue ProSAT]</span></td></tr> |
| </table> | | </table> |
| <div style="background-color:#fffaf0;">
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| == Publication Abstract from PubMed ==
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| The hairpin ribozyme requires functional group contributions from G8 to assist in phosphodiester bond cleavage. Previously, replacement of G8 by a series of nucleobase variants showed little effect on interdomain docking, but a 3-250-fold effect on catalysis. To identify G8 features that contribute to catalysis within the hairpin ribozyme active site, structures for five base variants were determined by X-ray crystallography in a resolution range between 2.3 and 2.7 A. For comparison, a native all-RNA "G8" hairpin ribozyme structure was refined to 2.05 A resolution. The native structure revealed a scissile bond angle (tau) of 158 degrees, which is close to the requisite 180 degrees "in-line" geometry. Mutations G8(inosine), G8(diaminopurine), G8(aminopurine), G8(adenosine), and G8(uridine) folded properly, but exhibited nonideal scissile bond geometries (tau ranging from 118 degrees to 93 degrees) that paralleled their diminished solution activities. A superposition ensemble of all structures, including a previously described hairpin ribozyme-vanadate complex, indicated the scissile bond can adopt a variety of conformations resulting from perturbation of the chemical environment and provided a rationale for how the exocyclic amine of nucleobase 8 promotes productive, in-line geometry. Changes at position 8 also caused variations in the A-1 sugar pucker. In this regard, variants A8 and U8 appeared to represent nonproductive ground states in which their 2'-OH groups mimicked the pro-R, nonbridging oxygen of the vanadate transition-state complex. Finally, the results indicated that ordered water molecules bind near the 2'-hydroxyl of A-1, lending support to the hypothesis that solvent may play an important role in the reaction.
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| Water in the active site of an all-RNA hairpin ribozyme and effects of Gua8 base variants on the geometry of phosphoryl transfer.,Salter J, Krucinska J, Alam S, Grum-Tokars V, Wedekind JE Biochemistry. 2006 Jan 24;45(3):686-700. PMID:16411744<ref>PMID:16411744</ref>
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| From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br>
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| </div>
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| <div class="pdbe-citations 2oue" style="background-color:#fffaf0;"></div>
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| ==See Also== | | ==See Also== |
| *[[Ribozyme 3D structures|Ribozyme 3D structures]] | | *[[Ribozyme 3D structures|Ribozyme 3D structures]] |
| == References ==
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| <references/>
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| __TOC__ | | __TOC__ |
| </StructureSection> | | </StructureSection> |
| [[Category: Large Structures]] | | [[Category: Large Structures]] |
| [[Category: Wedekind JE]] | | [[Category: Wedekind JE]] |
