Identification of a Peptide-Pheromone that Enhances Escape from Host Cell Vacuoles

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Experimental evidence has established that bacteria do not always exist as isolated single celled organisms, but instead communicate with each other through the secretion of small molecules that enable individual cells to coordinate complex traits and behaviors. Gram-positive bacteria rely on the secretion of small peptide pheromones to coordinate activities that include biofilm formation, exogenous DNA uptake via competence mechanisms, conjugal transfer of plasmid DNA, and expression of gene products that promote bacterial virulence. Here we provide evidence of a novel use of bacterial peptide pheromone signaling, that being the use of the pPplA peptide by L. monocytogenes to detect the confines of host cell vacuoles. Secretion and import of pPplA is required for efficient escape of L. monocytogenes from its initial membrane-bound host cell compartment, and bacteria lacking the peptide pheromone are severely attenuated for virulence in mice. The pPplA peptide pheromone is thus used by individual bacteria within a confined membrane bound space to coordinate the expression of gene products required by L. monocytogenes for intracellular growth and survival.

Vyšlo v časopise: Identification of a Peptide-Pheromone that Enhances Escape from Host Cell Vacuoles. PLoS Pathog 11(3): e32767. doi:10.1371/journal.ppat.1004707
Kategorie: Research Article
prolekare.web.journal.doi_sk: https://doi.org/10.1371/journal.ppat.1004707

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