Quorum Sensing and Self-Quorum Quenching in the Intracellular Pathogen Brucellamelitensis

• DOI: 10.1371/journal.pone.0082514
• Publication Date: 2013-12-11T21:30:30Z
• Authors: Matthieu Terwagne; Aurélie Mirabella; Julien Lemaire; Chantal Deschamps; Xavier De Bolle; Jean-Jacques Lete...
• Keywords: Flagellin; Autoinducer; Quorum Quenching

Brucella quorum sensing has been described as an important regulatory system controlling crucial virulence determinants such the VirB type IV secretion and flagellar genes. However, basis of sensing, namely production autoinducers in questioned. Here, we report data obtained from use a genetic tool allowing situ detection long-chain N-acyl-homoserine lactones (AHL) activity at single bacterium level melitensis. These are consistent with intrinsic AHL by B. melitensis low concentration both during vitro growth macrophage infection. Moreover, identified protein, named AibP, which is homologous to AHL-acylases various bacterial species. In infection, expression aibP coincided decrease endogenous within melitensis, suggesting that AibP could efficiently impair accumulation. Furthermore, showed deletion resulted enhanced virB genes VirB8 well reduced FlgE (hook protein) FliC (flagellin) vitro. Altogether, these results suggest AHL-dependent AHL-quorum quenching coexist Brucella, least regulate its virulence.