View source for 1exd


==CRYSTAL STRUCTURE OF A TIGHT-BINDING GLUTAMINE TRNA BOUND TO GLUTAMINE AMINOACYL TRNA SYNTHETASE==
<StructureSection load='1exd' size='340' side='right'caption='[[1exd]], [[Resolution|resolution]] 2.70&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1exd]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/"bacillus_coli"_migula_1895 "bacillus coli" migula 1895]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1EXD OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1EXD FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene></td></tr>
<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1qtq|1qtq]]</td></tr>
<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Glutamine--tRNA_ligase Glutamine--tRNA ligase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=6.1.1.18 6.1.1.18] </span></td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1exd FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1exd OCA], [http://pdbe.org/1exd PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1exd RCSB], [http://www.ebi.ac.uk/pdbsum/1exd PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=1exd ProSAT]</span></td></tr>
</table>
== Evolutionary Conservation ==
[[Image:Consurf_key_small.gif|200px|right]]
Check<jmol>
  <jmolCheckbox>
    <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/ex/1exd_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked>
    <text>to colour the structure by Evolutionary Conservation</text>
  </jmolCheckbox>
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=1exd ConSurf].
<div style="clear:both"></div>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Guided by an in vitro selection experiment designed to obtain tight binding aptamers of Escherichia coli glutamine specific tRNA (tRNAGln) for glutaminyl-tRNA synthetase (GlnRS), we have engineered a tRNA mutant in which the five-nucleotide variable loop sequence 5'-44CAUUC48-3' is replaced by 5'-44AGGU48-3'. This mutant tRNA binds to GlnRS with 30-fold improved affinity compared to the wild type. The 2.7 A cocrystal structure of the RNA aptamer-GlnRS complex reveals major rearrangements in the central tertiary core of the tRNA, while maintaining an RNA-protein interface identical to the wild type. The repacked RNA core features a novel hydrogen bonding arrangement of the trans Levitt pair G15-U48, a new sulfate binding pocket in the major groove, and increased hydrophobic stacking interactions among the bases. These data suggest that enhanced protein binding to a mutant globular RNA can arise from stabilization of RNA tertiary interactions rather than optimization of RNA-protein contacts.

Tertiary core rearrangements in a tight binding transfer RNA aptamer.,Bullock TL, Sherlin LD, Perona JJ Nat Struct Biol. 2000 Jun;7(6):497-504. PMID:10881199<ref>PMID:10881199</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 1exd" style="background-color:#fffaf0;"></div>

==See Also==
*[[Aminoacyl tRNA synthetase 3D structures|Aminoacyl tRNA synthetase 3D structures]]
*[[Transfer RNA (tRNA)|Transfer RNA (tRNA)]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Bacillus coli migula 1895]]
[[Category: Glutamine--tRNA ligase]]
[[Category: Large Structures]]
[[Category: Bullock, T L]]
[[Category: Perona, J J]]
[[Category: Sherlin, L D]]
[[Category: Engineered trna]]
[[Category: Ligase-rna complex]]
[[Category: Trna aptamer]]
[[Category: Trna-protein complex]]