In this study, we investigated the quorum sensing (QS) regulatory system of the psychrotrophic strain 94 isolated from spoiled refrigerated meat. The strain produced several -acyl--homoserine-lactone (AHL) QS signal molecules, with -(3-oxo-hexanoyl)--homoserine lactone and -(3-hydroxy-hexanoyl)--homoserine lactone as two main types. The and genes encoding an AHL synthase and a receptor regulatory protein, respectively, were cloned and sequenced.
View Article and Find Full Text PDFThe luxS gene is responsible for the synthesis of AI-2 (autoinducer-2), a signaling molecule that participates in quorum sensing regulation in a large number of bacteria. In this work, we investigated which phenotypes are regulated by luxS gene in Serratia proteamaculans 94, psychrotrophic strain isolated from spoiled refrigerated meat. AI-2 was identified in S.
View Article and Find Full Text PDFIn order to study the regulation of N-acyl-homoserine lactones synthesis (AHLs, the signal molecules of Quorum Sensing regulation) in Burkholderia cenocepacia strain 370 we obtained mutants with increased AHL production. One of the mutants, named BC-B6, was obtained by TnMod-RKm(r) plasposon mutagenesis. The plasposon insertion was located within the clpX gene encoding the ATPase subunit ClpX of the ClpXP protease.
View Article and Find Full Text PDFTo study the role of Quorum Sensing (QS) regulation in the control of the cellular processes of Burkholderia cenocepacia 370, plasmid pME6863 was transferred into its cells. The plasmid contains a heterologous gene encoding for AiiA N-acyl-homoserine lactonase, which degrades the signaling molecules of the QS system of N-acyl-homoserine lactones (AHL). An absence or reduction of AHL in the culture was revealed with the biosensors Chromobacterium violaceum CV026 and Agrobacterium tumifaciens NT1/pZLR4, respectively.
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