View source for 3noj


==The structure of HMG/CHA aldolase from the protocatechuate degradation pathway of Pseudomonas putida==
<StructureSection load='3noj' size='340' side='right'caption='[[3noj]], [[Resolution|resolution]] 1.82&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[3noj]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Pseudomonas_putida_F1 Pseudomonas putida F1]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3NOJ OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3NOJ 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]] 1.82&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=PG4:TETRAETHYLENE+GLYCOL'>PG4</scene>, <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=3noj FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3noj OCA], [https://pdbe.org/3noj PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3noj RCSB], [https://www.ebi.ac.uk/pdbsum/3noj PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3noj ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/HMGA_PSEP1 HMGA_PSEP1] Catalyzes the last step of the bacterial protocatechuate 4,5-cleavage pathway. The preferred substrates of the enzyme are 2-keto-4-hydroxy acids with a 4-carboxylate substitution. Catalyzes the conversion of 4-hydroxy-4-methyl-2-oxoglutarate (HMG) to pyruvate. Also catalyzes the conversion of 4-carboxy-4-hydroxy-2-oxoadipic acid (CHA) to pyruvate and oxaloacetate.<ref>PMID:20843800</ref> <ref>PMID:24359411</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/no/3noj_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=3noj ConSurf].
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== Publication Abstract from PubMed ==
HMG/CHA aldolase from Pseudomonas putida F1 catalyzes the last step of the bacterial protocatechuate 4,5- cleavage pathway. The enzyme's preferred substrates are 2-keto-4-hydroxy acids with a 4-carboxylate substitution. The enzyme also exhibits oxaloacetate decarboxylation and pyruvate alpha-proton exchange activity. Sodium oxalate is a competitive inhibitor of the aldolase reaction. The pH dependence of kcat/Km and kcat for the enzyme is consistent with a single deprotonation with pKa values of 8.0 +/- 0.1 and 7.0 +/- 0.1 for free enzyme and enzyme substrate complex, respectively. The 1.8 A x-ray structure shows a four-layered alpha-beta-beta-alpha sandwich structure with the active site at the interface of two adjacent subunits of a hexamer; this fold resembles the RNAse E inhibitor, RraA, but is novel for an aldolase. The catalytic site contains a magnesium ion ligated by Asp124 as well as three water molecules bound by Asp102 and Glu199. A pyruvate molecule binds the magnesium ion through both carboxylate and keto oxygen atoms, completing the octahedral geometry. The carbonyl oxygen also forms a hydrogen bonds with the guanadinium group of Arg123, which site-directed mutagenesis confirms is essential for catalysis. A mechanism for HMG/CHA aldolase is proposed on the basis of the structure, kinetics, and previously established features of other aldolase mechanisms.

Structural and kinetic characterization of 4-hydroxy-4-methyl-2-oxoglutarate (HMG)/4-carboxy-4-hydroxy-2-oxoadipate (CHA) aldolase: a protocatechuate degradation enzyme evolutionarily convergent with the HpaI and DmpG pyruvate aldolases.,Wang W, Mazurkewich S, Kimber MS, Seah SY J Biol Chem. 2010 Sep 15. PMID:20843800<ref>PMID:20843800</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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==See Also==
*[[Aldolase 3D structures|Aldolase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Pseudomonas putida F1]]
[[Category: Kimber MS]]
[[Category: Mazurkewich S]]
[[Category: Seah SYK]]
[[Category: Wang W]]