View source for 2r94


==Crystal Structure of KD(P)GA from T.tenax==
<StructureSection load='2r94' size='340' side='right'caption='[[2r94]], [[Resolution|resolution]] 2.20&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2r94]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Thermoproteus_tenax Thermoproteus tenax]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2R94 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2R94 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]] 2.2&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=PYR:PYRUVIC+ACID'>PYR</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=2r94 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2r94 OCA], [https://pdbe.org/2r94 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2r94 RCSB], [https://www.ebi.ac.uk/pdbsum/2r94 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2r94 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/KDGA_THETE KDGA_THETE] Involved in the degradation of glucose via the Entner-Doudoroff pathway. Catalyzes the reversible cleavage of 2-keto-3-deoxy-6-phosphogluconate (KDPG) and 2-keto-3-deoxygluconate (KDG) forming pyruvate and glyceraldehyde 3-phosphate or glyceraldehyde, respectively. It is not able to use 2-keto-3-deoxy-6-phosphogalactonate (KDPGal) and 2-keto-3-deoxygalactonate (KDGal) as substrate.<ref>PMID:15028704</ref> <ref>PMID:15869466</ref> <ref>PMID:18186475</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/r9/2r94_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=2r94 ConSurf].
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== Publication Abstract from PubMed ==
Carbon-carbon bond forming enzymes offer great potential for organic biosynthesis. Hence there is an ongoing effort to improve their biocatalytic properties, regarding availability, activity, stability, and substrate specificity and selectivity. Aldolases belong to the class of C-C bond forming enzymes and play important roles in numerous cellular processes. In several hyperthermophilic Archaea the 2-keto-3-deoxy-(6-phospho)-gluconate (KD(P)G) aldolase was identified as a key player in the metabolic pathway. The carbohydrate metabolism of the hyperthermophilic Crenarchaeote Thermoproteus tenax, for example, has been found to employ a combination of a variant of the Embden-Meyerhof-Parnas pathway and an unusual branched Entner-Doudoroff pathway that harbors a nonphosphorylative and a semiphosphorylative branch. The KD(P)G aldolase catalyzes the reversible cleavage of 2-keto-3-deoxy-6-phosphogluconate (KDPG) and 2-keto-3-deoxygluconate (KDG) forming pyruvate and glyceraldehyde 3-phosphate or glyceraldehyde, respectively. In T. tenax initial studies revealed that the pathway is specific for glucose, whereas in the thermoacidophilic Crenarchaeote Sulfolobus solfataricus the pathway was shown to be promiscuous for glucose and galactose degradation. The KD(P)G aldolase of S. solfataricus lacks stereo control and displays additional activity with 2-keto-3-deoxy-6-phosphogalactonate (KDPGal) and 2-keto-3-deoxygalactonate (KDGal), similar to the KD(P)G aldolase of Sulfolobus acidocaldarius. To address the stereo control of the T. tenax enzyme the formation of the two C4 epimers KDG and KDGal was analyzed via gas chromatography combined with mass spectroscopy. Furthermore, the crystal structure of the apoprotein was determined to a resolution of 2.0 A, and the crystal structure of the protein covalently linked to a pathway intermediate, namely pyruvate, was determined to 2.2 A. Interestingly, although the pathway seems to be specific for glucose in T. tenax the enzyme apparently also lacks stereo control, suggesting that the enzyme is a trade-off between required catabolic flexibility needed for the conversion of phosphorylated and nonphosphorylated substrates and required stereo control of cellular/physiological enzymatic reactions.

Crystal structure and stereochemical studies of KD(P)G aldolase from Thermoproteus tenax.,Pauluhn A, Ahmed H, Lorentzen E, Buchinger S, Schomburg D, Siebers B, Pohl E Proteins. 2008 Jul;72(1):35-43. PMID:18186475<ref>PMID:18186475</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 2r94" style="background-color:#fffaf0;"></div>

==See Also==
*[[Aldolase 3D structures|Aldolase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Thermoproteus tenax]]
[[Category: Pauluhn A]]
[[Category: Pohl E]]