3b8i

<StructureSection load='3b8i' size='340' side='right' caption='[[3b8i]], [[Resolution|resolution]] 1.90&Aring;' scene=''>

<table><tr><td colspan='2'>[[3b8i]] is a 6 chain structure with sequence from [http://en.wikipedia.org/wiki/Pseae Pseae]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3B8I OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3B8I FirstGlance]. <br>

</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=OXL:OXALATE+ION'>OXL</scene></td></tr>

<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">Dnase1 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=208964 PSEAE])</td></tr>

<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Oxaloacetate_decarboxylase Oxaloacetate decarboxylase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.1.1.3 4.1.1.3] </span></td></tr>

<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3b8i FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3b8i OCA], [http://pdbe.org/3b8i PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=3b8i RCSB], [http://www.ebi.ac.uk/pdbsum/3b8i PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=3b8i ProSAT]</span></td></tr>

[[http://www.uniprot.org/uniprot/OADC_PSEAE OADC_PSEAE]] Catalyzes the decarboxylation of oxaloacetate into pyruvate with high efficiency. Is also able to decarboxylate 3-methyloxaloacetate. Seems to play a role in maintaining cellular concentrations of bicarbonate and pyruvate.<ref>PMID:18081320</ref>

<div style="background-color:#fffaf0;">

== Publication Abstract from PubMed ==

Pseudomonas aeruginosa PA4872 was identified by sequence analysis as a structurally and functionally novel member of the PEP mutase/isocitrate lyase superfamily and therefore targeted for investigation. Substrate screens ruled out overlap with known catalytic functions of superfamily members. The crystal structure of PA4872 in complex with oxalate (a stable analogue of the shared family alpha-oxyanion carboxylate intermediate/transition state) and Mg2+ was determined at 1.9 A resolution. As with other PEP mutase/isocitrate lyase superfamily members, the protein assembles into a dimer of dimers with each subunit adopting an alpha/beta barrel fold and two subunits swapping their barrel's C-terminal alpha-helices. Mg2+ and oxalate bind in the same manner as observed with other superfamily members. The active site gating loop, known to play a catalytic role in the PEP mutase and lyase branches of the superfamily, adopts an open conformation. The Nepsilon of His235, an invariant residue in the PA4872 sequence family, is oriented toward a C(2) oxygen of oxalate analogous to the C(3) of a pyruvyl moiety. Deuterium exchange into alpha-oxocarboxylate-containing compounds was confirmed by 1H NMR spectroscopy. Having ruled out known activities, the involvement of a pyruvate enolate intermediate suggested a decarboxylase activity of an alpha-oxocarboxylate substrate. Enzymatic assays led to the discovery that PA4872 decarboxylates oxaloacetate (kcat = 7500 s(-1) and Km = 2.2 mM) and 3-methyloxaloacetate (kcat = 250 s(-1) and Km = 0.63 mM). Genome context of the fourteen sequence family members indicates that the enzyme is used by select group of Gram-negative bacteria to maintain cellular concentrations of bicarbonate and pyruvate; however the decarboxylation activity cannot be attributed to a pathway common to the various bacterial species.

Structure and function of PA4872 from Pseudomonas aeruginosa, a novel class of oxaloacetate decarboxylase from the PEP mutase/isocitrate lyase superfamily.,Narayanan BC, Niu W, Han Y, Zou J, Mariano PS, Dunaway-Mariano D, Herzberg O Biochemistry. 2008 Jan 8;47(1):167-82. Epub 2007 Dec 15. PMID:18081320<ref>PMID:18081320</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 3b8i" style="background-color:#fffaf0;"></div>

[[Category: Oxaloacetate decarboxylase]]

[[Category: Pseae]]

[[Category: Herzberg, O]]

[[Category: Narayanan, B C]]

[[Category: Lyase]]