View source for 3gei


==Crystal structure of MnmE from Chlorobium tepidum in complex with GCP==
<StructureSection load='3gei' size='340' side='right'caption='[[3gei]], [[Resolution|resolution]] 3.40&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[3gei]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Chlorobaculum_tepidum Chlorobaculum tepidum]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3GEI OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3GEI 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]] 3.4&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=GCP:PHOSPHOMETHYLPHOSPHONIC+ACID+GUANYLATE+ESTER'>GCP</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</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=3gei FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3gei OCA], [https://pdbe.org/3gei PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3gei RCSB], [https://www.ebi.ac.uk/pdbsum/3gei PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3gei ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/MNME_CHLTE MNME_CHLTE] Exhibits a very high intrinsic GTPase hydrolysis rate. Involved in the addition of a carboxymethylaminomethyl (cmnm) group at the wobble position (U34) of certain tRNAs, forming tRNA-cmnm(5)s(2)U34.[HAMAP-Rule:MF_00379]
== 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/ge/3gei_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=3gei ConSurf].
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== Publication Abstract from PubMed ==
MnmE, which is involved in the modification of the wobble position of certain tRNAs, belongs to the expanding class of G proteins activated by nucleotide-dependent dimerization (GADs). Previous models suggested the protein to be a multidomain protein whose G domains contact each other in a nucleotide dependent manner. Here we employ a combined approach of X-ray crystallography and pulse electron paramagnetic resonance (EPR) spectroscopy to show that large domain movements are coupled to the G protein cycle of MnmE. The X-ray structures show MnmE to be a constitutive homodimer where the highly mobile G domains face each other in various orientations but are not in close contact as suggested by the GDP-AlF(x) structure of the isolated domains. Distance measurements by pulse double electron-electron resonance (DEER) spectroscopy show that the G domains adopt an open conformation in the nucleotide free/GDP-bound and an open/closed two-state equilibrium in the GTP-bound state, with maximal distance variations of 18 A. With GDP and AlF(x), which mimic the transition state of the phosphoryl transfer reaction, only the closed conformation is observed. Dimerization of the active sites with GDP-AlF(x) requires the presence of specific monovalent cations, thus reflecting the requirements for the GTPase reaction of MnmE. Our results directly demonstrate the nature of the conformational changes MnmE was previously suggested to undergo during its GTPase cycle. They show the nucleotide-dependent dynamic movements of the G domains around two swivel positions relative to the rest of the protein, and they are of crucial importance for understanding the mechanistic principles of this GAD.

Kissing G domains of MnmE monitored by X-ray crystallography and pulse electron paramagnetic resonance spectroscopy.,Meyer S, Bohme S, Kruger A, Steinhoff HJ, Klare JP, Wittinghofer A PLoS Biol. 2009 Oct;7(10):e1000212. Epub 2009 Oct 6. PMID:19806182<ref>PMID:19806182</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 3gei" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Chlorobaculum tepidum]]
[[Category: Large Structures]]
[[Category: Meyer S]]
[[Category: Wittinghofer A]]