View source for 4o98


==Crystal structure of Pseudomonas oleovorans PoOPH mutant H250I/I263W==
<StructureSection load='4o98' size='340' side='right'caption='[[4o98]], [[Resolution|resolution]] 2.25&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4o98]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Pseudomonas_oleovorans Pseudomonas oleovorans]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4O98 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4O98 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]] 2.251&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ZN:ZINC+ION'>ZN</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=4o98 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4o98 OCA], [https://pdbe.org/4o98 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4o98 RCSB], [https://www.ebi.ac.uk/pdbsum/4o98 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4o98 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/A0A0B4J186_PSEOL A0A0B4J186_PSEOL] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
OPHC2 is a thermostable organophosphate (OP) hydrolase in the beta-lactamase superfamily. OPs are highly toxic synthetic chemicals with no natural analogs. How did OPHC2 acquire phosphotriesterase (PTE) activity remained unclear. In this study, an OPHC2 analogue, PoOPH was discovered from Pseudomonas oleovorans exhibiting high lactonase and esterase activities and latent PTE activity. Sequence analysis revealed conserved His250 and Ile263 and site-directed mutagenesis at these crucial residues enhanced PTE activity. The best variant PoOPHM2 carrying H250I/I263W mutations displayed 6,962- and 106-fold improvements in catalytic efficiency for methyl-parathion and ethyl-paraoxon degradation, whereas the original lactonase and esterase activities decreased dramatically. A 1.4 x 10(7) -fold of specificity inversion was achieved by only two residue substitutions. Significantly, thermostability of the variants was not compromised. Crystal structure of PoOPHM2 was determined at 2.25 A resolution and docking studies suggested that the two residues in the binding pocket determine substrate recognition. Lastly, new organophosphorus hydrolases (OPHs) were discovered using simple double mutations. Among them, PpOPHM2 from Pseudomonas putida emerged as a new promising OPH with very high activity (41.0 U mg(-1) ) toward methyl-parathion. Our results offer a first scrutiny to PTE activity evolution of OPHs in beta-lactamase superfamily and provide efficient and robust enzymes for OP detoxification.

Switching a newly discovered lactonase into an efficient and thermostable phosphotriesterase by simple double mutations His250Ile/Ile263Trp.,Luo XJ, Kong XD, Zhao J, Chen Q, Zhou J, Xu JH Biotechnol Bioeng. 2014 Oct;111(10):1920-30. doi: 10.1002/bit.25272. Epub 2014, Jul 14. PMID:24771278<ref>PMID:24771278</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4o98" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Pseudomonas oleovorans]]
[[Category: Chen Q]]
[[Category: Kong XD]]
[[Category: Luo XJ]]
[[Category: Xu JH]]
[[Category: Zhao J]]
[[Category: Zhou JH]]