4zo2: Difference between revisions
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''' | ==AidC, a Dizinc Quorum-Quenching Lactonase== | ||
<StructureSection load='4zo2' size='340' side='right' caption='[[4zo2]], [[Resolution|resolution]] 1.09Å' scene=''> | |||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[4zo2]] is a 2 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4ZO2 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4ZO2 FirstGlance]. <br> | |||
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr> | |||
<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[4zo3|4zo3]]</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=4zo2 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4zo2 OCA], [http://www.rcsb.org/pdb/explore.do?structureId=4zo2 RCSB], [http://www.ebi.ac.uk/pdbsum/4zo2 PDBsum]</span></td></tr> | |||
</table> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
Quorum-quenching catalysts are of interest for potential application as biochemical tools for interrogating interbacterial communication pathways, as antibiofouling agents, and as anti-infective agents in plants and animals. Herein, the structure and function of AidC, an N-acyl-l-homoserine lactone (AHL) lactonase from Chryseobacterium, is characterized. Steady-state kinetics show that zinc-supplemented AidC is the most efficient wild-type quorum-quenching enzymes characterized to date, with a kcat/KM value of approximately 2 x 106 M-1 s-1 for N-heptanoyl-l-homoserine lactone. The enzyme has stricter substrate selectivity and significantly lower KM values (ca. 50 muM for preferred substrates) compared to those of typical AHL lactonases (ca. >1 mM). X-ray crystal structures of AidC alone and with the product N-hexanoyl-l-homoserine were determined at resolutions of 1.09 and 1.67 A, respectively. Each structure displays as a dimer, and dimeric oligiomerization was also observed in solution by size-exclusion chromatography coupled with multiangle light scattering. The structures reveal two atypical features as compared to previously characterized AHL lactonases: a "kinked" alpha-helix that forms part of a closed binding pocket that provides affinity and enforces selectivity for AHL substrates and an active-site His substitution that is usually found in a homologous family of phosphodiesterases. Implications for the catalytic mechanism of AHL lactonases are discussed. | |||
Structural and Biochemical Characterization of AidC, a Quorum-Quenching Lactonase with Atypical Selectivity.,Mascarenhas R, Thomas PW, Wu CX, Nocek BP, Hoang QQ, Liu D, Fast W Biochemistry. 2015 Jul 8. PMID:26115006<ref>PMID:26115006</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
== References == | |||
<references/> | |||
[[Category: | __TOC__ | ||
</StructureSection> | |||
[[Category: Fast, W]] | |||
[[Category: Hoang, Q]] | [[Category: Hoang, Q]] | ||
[[Category: Liu, D]] | [[Category: Liu, D]] | ||
[[Category: Mascarenhas, R]] | [[Category: Mascarenhas, R]] | ||
[[Category: Nocek, B P]] | |||
[[Category: Thomas, P W]] | |||
[[Category: Wu, C X]] | |||
[[Category: Dizinc]] | |||
[[Category: Hydrolase]] | |||
[[Category: Lactonase]] | |||
[[Category: N-acyl-l-homoserine lactone]] | |||
[[Category: Quorum-quenching]] | |||
Revision as of 16:21, 15 July 2015
AidC, a Dizinc Quorum-Quenching LactonaseAidC, a Dizinc Quorum-Quenching Lactonase
Structural highlights
Publication Abstract from PubMedQuorum-quenching catalysts are of interest for potential application as biochemical tools for interrogating interbacterial communication pathways, as antibiofouling agents, and as anti-infective agents in plants and animals. Herein, the structure and function of AidC, an N-acyl-l-homoserine lactone (AHL) lactonase from Chryseobacterium, is characterized. Steady-state kinetics show that zinc-supplemented AidC is the most efficient wild-type quorum-quenching enzymes characterized to date, with a kcat/KM value of approximately 2 x 106 M-1 s-1 for N-heptanoyl-l-homoserine lactone. The enzyme has stricter substrate selectivity and significantly lower KM values (ca. 50 muM for preferred substrates) compared to those of typical AHL lactonases (ca. >1 mM). X-ray crystal structures of AidC alone and with the product N-hexanoyl-l-homoserine were determined at resolutions of 1.09 and 1.67 A, respectively. Each structure displays as a dimer, and dimeric oligiomerization was also observed in solution by size-exclusion chromatography coupled with multiangle light scattering. The structures reveal two atypical features as compared to previously characterized AHL lactonases: a "kinked" alpha-helix that forms part of a closed binding pocket that provides affinity and enforces selectivity for AHL substrates and an active-site His substitution that is usually found in a homologous family of phosphodiesterases. Implications for the catalytic mechanism of AHL lactonases are discussed. Structural and Biochemical Characterization of AidC, a Quorum-Quenching Lactonase with Atypical Selectivity.,Mascarenhas R, Thomas PW, Wu CX, Nocek BP, Hoang QQ, Liu D, Fast W Biochemistry. 2015 Jul 8. PMID:26115006[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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