title: Orally administered thermostable N-acyl homoserine lactonase from Bacillus sp. strain AI96 attenuates Aeromonas hydrophila infection in zebrafish.
abstract: N-Acylated homoserine lactone (AHL) lactonases are capable of degrading signal molecules involved in bacterial quorum sensing and therefore represent a new approach to control bacterial infection. Here a gene responsible for the AHL lactonase activity of Bacillus sp. strain AI96, 753 bp in length, was cloned and then expressed in Escherichia coli. The deduced amino acid sequence of Bacillus sp. AI96 AiiA (AiiA(AI96)) is most similar to those of other Bacillus sp. AHL lactonases (~80% sequence identity) and was consequently categorized as a member of the metallo-β-lactamase superfamily. AiiA(AI96) maintains ~100% of its activity at 10°C to 40°C at pH 8.0, and it is very stable at 70°C at pH 8.0 for at least 1 h; no other Bacillus AHL lactonase has been found to be stable under these conditions. AiiA(AI96) resists digestion by proteases and carp intestinal juice, and it has broad-spectrum substrate specificity. The supplementation of AiiA(AI96) into fish feed by oral administration significantly attenuated Aeromonas hydrophila infection in zebrafish. This is the first report of the oral administration of an AHL lactonase for the efficient control of A. hydrophila.
authors.affiliation: Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, People’s Republic of China.
authors.forename: Yanan
authors.initials: Y
authors.lastname: Cao
authors.forename: Suxu
authors.initials: S
authors.lastname: He
authors.forename: Zhigang
authors.initials: Z
authors.lastname: Zhou
authors.forename: Meichao
authors.initials: M
authors.lastname: Zhang
authors.forename: Wei
authors.initials: W
authors.lastname: Mao
authors.forename: Huitu
authors.initials: H
authors.lastname: Zhang
authors.forename: Bin
authors.initials: B
authors.lastname: Yao
mesh_terms: D016980:Aeromonas hydrophila / Q000187:drug effects* / Q000254:growth & development*; D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage* / Q000302:isolation & purification; D001407:Bacillus / Q000201:enzymology*; D002265:Carboxylic Ester Hydrolases / Q000008:administration & dosage* / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004795:Enzyme Stability; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D013379:Substrate Specificity; D013696:Temperature; D013997:Time Factors; D015027:Zebrafish / Q000382:microbiology*
chemical_list: D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; D002265:Carboxylic Ester Hydrolases; C432003:N-acyl homoserine lactonase