3DHB

1.4 Angstrom Structure of N-Acyl Homoserine Lactone Hydrolase with the Product N-Hexanoyl-L-Homoserine Bound at The Catalytic Metal Center

Summary for 3DHB

• Entry DOI: 10.2210/pdb3dhb/pdb
• Related: 2A7M 2R2D 3DHA 3DHC
• Descriptor: N-Acyl Homoserine Lactone Hydrolase, ZINC ION, N-hexanoyl-L-homoserine, ... (5 entities in total)
• Functional Keywords: zinc bimetallohydrolase, qourum quenching, n-acyl homoserine lactone, product complex, ahl lactonase, general acid, catalytic mechanism, hydrolase
• Biological source: Bacillus thuringiensis serovar kurstaki
• Total number of polymer chains: 1
• Total formula weight: 29657.38

Authors

Liu, D.,Momb, J.,Thomas, P.W.,Moulin, A.,Petsko, G.A.,Fast, W.,Ringe, D. (deposition date: 2008-06-17, release date: 2008-07-29, Last modification date: 2023-08-30)

Primary citation

Liu, D.,Momb, J.,Thomas, P.W.,Moulin, A.,Petsko, G.A.,Fast, W.,Ringe, D.
Mechanism of the quorum-quenching lactonase (AiiA) from Bacillus thuringiensis. 1. Product-bound structures.
Biochemistry, 47:7706-7714, 2008

PubMed Abstract: Enzymes capable of hydrolyzing N-acyl- l-homoserine lactones (AHLs) used in some bacterial quorum-sensing pathways are of considerable interest for their ability to block undesirable phenotypes. Most known AHL hydrolases that catalyze ring opening (AHL lactonases) are members of the metallo-beta-lactamase enzyme superfamily and rely on a dinuclear zinc site for catalysis and stability. Here we report the three-dimensional structures of three product complexes formed with the AHL lactonase from Bacillus thuringiensis. Structures of the lactonase bound with two different concentrations of the ring-opened product of N-hexanoyl- l-homoserine lactone are determined at 0.95 and 1.4 A resolution and exhibit different product configurations. A structure of the ring-opened product of the non-natural N-hexanoyl- l-homocysteine thiolactone at 1.3 A resolution is also determined. On the basis of these product-bound structures, a substrate-binding model is presented that differs from previous proposals. Additionally, the proximity of the product to active-site residues and observed changes in protein conformation and metal coordination provide insight into the catalytic mechanism of this quorum-quenching metalloenzyme.

PubMed: 18627129
DOI: 10.1021/bi800368y

Experimental method

X-RAY DIFFRACTION (1.4 Å)