2r2d

From Proteopedia

Revision as of 16:44, 21 February 2008 by OCA (Talk | contribs)
Jump to: navigation, search

2r2d, resolution 1.75Å

Drag the structure with the mouse to rotate

Structure of a quorum-quenching lactonase (AiiB) from Agrobacterium tumefaciens

Overview

N-Acyl-l-homoserine lactone (AHL) mediated quorum-sensing regulates virulence factor production in a variety of Gram-negative bacteria. Proteins capable of degrading these autoinducers have been called "quorum-quenching" enzymes, can block many quorum-sensing dependent phenotypes, and represent potentially useful reagents for clinical, agricultural, and industrial applications. The most characterized quorum-quenching enzymes to date are the AHL lactonases, which are metalloproteins that belong to the metallo-beta-lactamase superfamily. Here, we report the cloning, heterologous expression, purification, metal content, substrate specificity, and three-dimensional structure of AiiB, an AHL lactonase from Agrobacterium tumefaciens. Much like a homologous AHL lactonase from Bacillus thuringiensis, AiiB appears to be a metal-dependent AHL lactonase with broad specificity. A phosphate dianion is bound to the dinuclear zinc site and the active-site structure suggests specific mechanistic roles for an active site tyrosine and aspartate. To our knowledge, this is the second representative structure of an AHL lactonase and the first of an AHL lactonase from a microorganism that also produces AHL autoinducers. This work should help elucidate the hydrolytic ring-opening mechanism of this family of enzymes and also facilitate the design of more effective quorum-quenching catalysts.

About this Structure

2R2D is a Single protein structure of sequence from Agrobacterium tumefaciens with , and as ligands. Known structural/functional Sites: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , and . Full crystallographic information is available from OCA.

Reference

Structure and specificity of a quorum-quenching lactonase (AiiB) from Agrobacterium tumefaciens., Liu D, Thomas PW, Momb J, Hoang QQ, Petsko GA, Ringe D, Fast W, Biochemistry. 2007 Oct 23;46(42):11789-99. Epub 2007 Sep 28. PMID:17900178

Page seeded by OCA on Thu Feb 21 18:44:05 2008

Proteopedia Page Contributors and Editors (what is this?)

OCA

Personal tools