View source for 5vxf


==Crystal structure of Xanthomonas campestris OleA E117Q==
<StructureSection load='5vxf' size='340' side='right'caption='[[5vxf]], [[Resolution|resolution]] 1.75&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[5vxf]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Xanthomonas_campestris_pv._campestris_str._ATCC_33913 Xanthomonas campestris pv. campestris str. ATCC 33913]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5VXF OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=5VXF 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]] 1.75&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=GOL:GLYCEROL'>GOL</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=5vxf FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5vxf OCA], [https://pdbe.org/5vxf PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=5vxf RCSB], [https://www.ebi.ac.uk/pdbsum/5vxf PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=5vxf ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/OLEA_XANCP OLEA_XANCP] Involved in olefin biosynthesis (PubMed:21266575, PubMed:22524624, PubMed:27815501, PubMed:28223313). Catalyzes a non-decarboxylative head-to-head Claisen condensation of two acyl-CoA molecules, generating an (R)-2-alkyl-3-oxoalkanoate (PubMed:21266575, PubMed:22524624, PubMed:27815501). Is active with fatty acyl-CoA substrates that ranged from C(8) to C(16) in length, and is the most active with palmitoyl-CoA and myristoyl-CoA (PubMed:21266575).<ref>PMID:21266575</ref> <ref>PMID:22524624</ref> <ref>PMID:27815501</ref> <ref>PMID:28223313</ref> 
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== Publication Abstract from PubMed ==
In the interest of decreasing dependence on fossil fuels, microbial hydrocarbon biosynthesis pathways are being studied for renewable, tailored production of specialty chemicals and biofuels. One candidate is long-chain olefin biosynthesis, a widespread bacterial pathway that produces waxy hydrocarbons. Found in three- and four-gene clusters, oleABCD encode the enzymes necessary to produce cis -olefins that differ by alkyl chain length, degree of unsaturation, and alkyl chain branching. The first enzyme in the pathway, OleA, catalyzes the Claisen condensation of two fatty acyl-coenzyme A molecules to form a beta-keto acid. In this report, the mechanistic role of Xanthomonas campestris OleA Glu117 is investigated through mutant enzymes. Crystal structures were determined for each mutant as well as their complex with the inhibitor cerulenin. Complemented by substrate modelling, these structures suggest that Glu117 aids in substrate positioning for productive carbon-carbon bond formation. Analysis of acyl-coenzyme A substrate hydrolysis shows diminished activity in all mutants. When the active site lacks an acidic residue in the 117 position, OleA cannot form condensed product, demonstrating Glu117 has a critical role upstream of the essential condensation reaction. Profiling of pH dependence shows that the apparent pKa for Glu117 is impacted by mutagenesis. Taken together, we propose that Glu117 is the general base needed to prime condensation via deprotonation of the second, non-covalently bound substrate during turnover. This is the first example of a member of the thiolase superfamily of condensing enzymes to contain an active site base originating from the second monomer of the dimer.

OleA Glu117 is key to condensation of two fatty-acyl coenzyme A substrates in long-chain olefin biosynthesis.,Jensen MR, Goblirsch BR, Christenson JK, Esler MA, Mohamed FA, Wackett LP, Wilmot CM Biochem J. 2017 Oct 12. pii: BCJ20170642. doi: 10.1042/BCJ20170642. PMID:29025976<ref>PMID:29025976</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 5vxf" style="background-color:#fffaf0;"></div>

==See Also==
*[[Acyl carrier protein synthase 3D structures|Acyl carrier protein synthase 3D structures]]
== References ==
<references/>
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</StructureSection>
[[Category: Large Structures]]
[[Category: Xanthomonas campestris pv. campestris str. ATCC 33913]]
[[Category: Jensen MR]]
[[Category: Wilmot CM]]