title: BpiB05, a novel metagenome-derived hydrolase acting on N-acylhomoserine lactones.
abstract: The N-acyl-homoserine lactones (N-AHLs) play an important role in bacterial cell-cell signaling. Up to date, however, only a few different experimentally proven classes of N-AHL ring-cleaving enzymes are known. Here we report on the isolation and biochemical characterization of a novel hydrolase derived from the soil metagenome and acting on N-AHLs. The identified protein designated BpiB05 is weakly similar to hypothetical proteins from Bacteroides fragilis, the draft genomes of two Burkholderia species as well as a marine metagenomic ORF but is otherwise not similar to any known protein. BpiB05 was overexpressed in Escherichia coli as a 10× His-tagged fusion protein. The recombinant protein revealed a molecular weight of about 70kDa and was tested for its quorum quenching (QQ) activities using a lacZ-bioassay. Additional HPLC-MS analyses confirmed the lactonolytic activity of the purified protein in the presence of Ca²⁺. Further tests suggested that BpiB05 strongly reduces motility in Pseudomonas aeruginosa, pyocyanin synthesis and biofilm formation in this microbe. Because BpiB05 is not distantly related to any of the currently known hydrolases it forms probably a novel group within the growing number of proteins acting on N-AHLs.
authors.affiliation: Abteilung für Mikrobiologie und Biotechnologie, Biozentrum Klein Flottbek, Universität Hamburg, Ohnhorststr. 18, D-22609 Hamburg, Germany.
authors.forename: P
authors.initials: P
authors.lastname: Bijtenhoorn
authors.forename: C
authors.initials: C
authors.lastname: Schipper
authors.forename: C
authors.initials: C
authors.lastname: Hornung
authors.forename: M
authors.initials: M
authors.lastname: Quitschau
authors.forename: S
authors.initials: S
authors.lastname: Grond
authors.forename: N
authors.initials: N
authors.lastname: Weiland
authors.forename: W R
authors.initials: WR
authors.lastname: Streit
mesh_terms: D054742:Acyl-Butyrolactones / Q000378:metabolism*; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D001441:Bacteroides fragilis / Q000235:genetics; D018441:Biofilms / Q000187:drug effects; D019117:Burkholderia / Q000235:genetics; D002851:Chromatography, High Pressure Liquid; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D006867:Hydrolases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D013058:Mass Spectrometry; D054892:Metagenome; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D053038:Quorum Sensing; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology; D012988:Soil Microbiology; D001616:beta-Galactosidase
chemical_list: D054742:Acyl-Butyrolactones; D001426:Bacterial Proteins; D011993:Recombinant Fusion Proteins; D006867:Hydrolases; D001616:beta-Galactosidase