View source for 2a8x


==Crystal Structure of Lipoamide Dehydrogenase from Mycobacterium tuberculosis==
<StructureSection load='2a8x' size='340' side='right'caption='[[2a8x]], [[Resolution|resolution]] 2.40&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2a8x]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Mycobacterium_tuberculosis Mycobacterium tuberculosis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2A8X OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2A8X 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]] 2.4&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=FAD:FLAVIN-ADENINE+DINUCLEOTIDE'>FAD</scene>, <scene name='pdbligand=MPD:(4S)-2-METHYL-2,4-PENTANEDIOL'>MPD</scene>, <scene name='pdbligand=MSE:SELENOMETHIONINE'>MSE</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=2a8x FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2a8x OCA], [https://pdbe.org/2a8x PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2a8x RCSB], [https://www.ebi.ac.uk/pdbsum/2a8x PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2a8x ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/DLDH_MYCTU DLDH_MYCTU] Lipoamide dehydrogenase is an essential component of the alpha-ketoacid dehydrogenase complexes, namely the pyruvate dehydrogenase (PDH) complex, the branched-chain alpha-ketoacid dehydrogenase (BCKADH) complex, and likely also the 2-oxoglutarate dehydrogenase (ODH) complex. Catalyzes the reoxidation of dihydrolipoyl groups which are covalently attached to the lipoate acyltransferase components (E2) of the complexes. Is also able to catalyze the transhydrogenation of NADH and thio-NAD(+) in the absence of D,L-lipoamide, and the NADH-dependent reduction of quinones in vitro.<ref>PMID:11560483</ref> <ref>PMID:11799204</ref> <ref>PMID:16045627</ref> <ref>PMID:21238944</ref> <ref>PMID:16093239</ref>   Together with AhpC, AhpD and DlaT, Lpd constitutes an NADH-dependent peroxidase active against hydrogen and alkyl peroxides as well as serving as a peroxynitrite reductase, thus protecting the bacterium against reactive nitrogen intermediates and oxidative stress generated by the host immune system.<ref>PMID:11560483</ref> <ref>PMID:11799204</ref> <ref>PMID:16045627</ref> <ref>PMID:21238944</ref> <ref>PMID:16093239</ref>   Appears to be essential for Mtb pathogenesis.<ref>PMID:11560483</ref> <ref>PMID:11799204</ref> <ref>PMID:16045627</ref> <ref>PMID:21238944</ref> <ref>PMID:16093239</ref> 
== 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/a8/2a8x_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview03.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=2a8x ConSurf].
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== Publication Abstract from PubMed ==
We report the 2.4 A crystal structure for lipoamide dehydrogenase encoded by lpdC from Mycobacterium tuberculosis. Based on the Lpd structure and sequence alignment between bacterial and eukaryotic Lpd sequences, we generated single point mutations in Lpd and assayed the resulting proteins for their ability to catalyze lipoamide reduction/oxidation alone and in complex with other proteins that participate in pyruvate dehydrogenase and peroxidase activities. The results suggest that amino acid residues conserved in mycobacterial species but not conserved in eukaryotic Lpd family members modulate either or both activities and include Arg-93, His-98, Lys-103, and His-386. In addition, Arg-93 and His-386 are involved in forming both "open" and "closed" active site conformations, suggesting that these residues play a role in dynamically regulating Lpd function. Taken together, these data suggest protein surfaces that should be considered while developing strategies for inhibiting this enzyme.

Crystal structure and functional analysis of lipoamide dehydrogenase from Mycobacterium tuberculosis.,Rajashankar KR, Bryk R, Kniewel R, Buglino JA, Nathan CF, Lima CD J Biol Chem. 2005 Oct 7;280(40):33977-83. Epub 2005 Aug 10. PMID:16093239<ref>PMID:16093239</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 2a8x" style="background-color:#fffaf0;"></div>

==See Also==
*[[Dihydrolipoamide dehydrogenase|Dihydrolipoamide dehydrogenase]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Mycobacterium tuberculosis]]
[[Category: Bryk R]]
[[Category: Buglino JA]]
[[Category: Kniewel R]]
[[Category: Lima CD]]
[[Category: Nathan CF]]
[[Category: Rajashankar KR]]