View source for 4cqn


==Crystal structure of the E.coli LeuRS-tRNA complex with the non- cognate isoleucyl adenylate analogue==
<StructureSection load='4cqn' size='340' side='right'caption='[[4cqn]], [[Resolution|resolution]] 2.50&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4cqn]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] and [https://en.wikipedia.org/wiki/Escherichia_coli_K-12 Escherichia coli K-12]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4CQN OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4CQN FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.5&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ILA:N-[ISOLEUCINYL]-N-[ADENOSYL]-DIAMINOSUFONE'>ILA</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></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=4cqn FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4cqn OCA], [https://pdbe.org/4cqn PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4cqn RCSB], [https://www.ebi.ac.uk/pdbsum/4cqn PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4cqn ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/SYL_ECOLI SYL_ECOLI] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The fidelity of protein synthesis depends on the capacity of aminoacyl-tRNA synthetases (AARSs) to couple only cognate amino acid-tRNA pairs. If amino acid selectivity is compromised, fidelity can be ensured by an inherent AARS editing activity that hydrolyses mischarged tRNAs. Here, we show that the editing activity of Escherichia coli leucyl-tRNA synthetase (EcLeuRS) is not required to prevent incorrect isoleucine incorporation. Rather, as shown by kinetic, structural and in vivo approaches, the prime biological function of LeuRS editing is to prevent mis-incorporation of the non-standard amino acid norvaline. This conclusion follows from a reassessment of the discriminatory power of LeuRS against isoleucine and the demonstration that a LeuRS editing-deficient E. coli strain grows normally in high concentrations of isoleucine but not under oxygen deprivation conditions when norvaline accumulates to substantial levels. Thus, AARS-based translational quality control is a key feature for bacterial adaptive response to oxygen deprivation. The non-essential role for editing under normal bacterial growth has important implications for the development of resistance to antimicrobial agents targeting the LeuRS editing site.

The physiological target for LeuRS translational quality control is norvaline.,Cvetesic N, Palencia A, Halasz I, Cusack S, Gruic-Sovulj I EMBO J. 2014 Jun 16. pii: e201488199. PMID:24935946<ref>PMID:24935946</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4cqn" 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: Escherichia coli]]
[[Category: Escherichia coli K-12]]
[[Category: Large Structures]]
[[Category: Cusack S]]
[[Category: Cvetesic N]]
[[Category: Gruic-Sovulj I]]
[[Category: Haslaz I]]
[[Category: Palencia A]]