title: Design of N-acyl homoserine lactonase with high substrate specificity by a rational approach.
abstract: N-Acyl homoserine lactone (AHL) is a major quorum-sensing signaling molecule in many bacterial species. Quorum-quenching (QQ) enzymes, which degrade such signaling molecules, have attracted much attention as an approach to controlling and preventing bacterial virulence and pathogenesis. However, naturally occurring QQ enzymes show a broad substrate spectrum, raising the concern of unintentionally attenuating beneficial effects by symbiotic bacteria. Here we report the rational design of acyl homoserine lactonase with high substrate specificity. Through docking analysis, we identified three key residues which play a key role in the substrate preference of the enzyme. The key residues were changed in a way that increases hydrophobic contact with a substrate having a short acyl chain (C4-AHL) while generating steric clashes with that containing a long acyl chain (C12-AHL). The resulting mutants exhibited a significantly shifted preference toward a substrate with a short acyl chain. Molecular dynamics simulations suggested that the mutations affect the behavior of a flexible loop, allowing tighter binding of a substrate with a short acyl chain.
authors.affiliation: Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, 305-701, Korea.
authors.forename: Hyun-Ho
authors.initials: HH
authors.lastname: Kyeong
authors.forename: Jin-Hyun
authors.initials: JH
authors.lastname: Kim
authors.forename: Hak-Sung
authors.initials: HS
authors.lastname: Kim
mesh_terms: D054742:Acyl-Butyrolactones / Q000378:metabolism*; D002265:Carboxylic Ester Hydrolases / Q000235:genetics* / Q000378:metabolism*; D007700:Kinetics; D008958:Models, Molecular; D062105:Molecular Docking Simulation; D050505:Mutant Proteins / Q000235:genetics / Q000378:metabolism*; D013379:Substrate Specificity
chemical_list: D054742:Acyl-Butyrolactones; D050505:Mutant Proteins; D002265:Carboxylic Ester Hydrolases; C432003:N-acyl homoserine lactonase