3.5.1.97 H278S site-directed mutagenesis, the mutant shows 80% reduced activity compared to wild-type 3.5.1.97 L279S site-directed mutagenesis, the mutant shows 74% reduced activity compared to wild-type 3.5.1.97 additional information the strain PAO1-DELTApvd is shown to be more virulent than the wild-type strain, confirming the role of PvdQ as a virulence-reducing agent 3.5.1.97 additional information random transposon mutagenesis, screening of the resulting mutants for the loss of AHL acylase activity. The Tn insertion in mutant A6731 is mapped to a gene termed aiiO 3.5.1.97 additional information AHL-mediated virulence factor production in a plant pathogen, Pectobacterium carotovorum, is dramatically attenuated by coculture with MacQ-overexpressing Escherichia coli Origami 2(DE3), whereas Escherichia coli with an empty vector is unable to quench the pathogenicity