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Regulated expression of pathogen-associated molecular pattern molecules in Staphylococcus epidermidis: quorum-sensing determines pro-inflammatory capacity and production of phenol-soluble modulins.

Cuong Vuong·Manuela Dürr·Aaron B Carmody·Andreas Peschel·Seymour J Klebanoff·Michael Otto
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Abstract

Phenol-soluble modulin (PSM) is a peptide complex produced by the nosocomial pathogen Staphylococcus epidermidis that has a strong capacity to activate the human innate immune response. We developed a novel method based on liquid chromatography-mass spectrometry (LC-MS) to quantify the production of the individual PSM components. Each PSM peptide was abundant in most of the 76 S epidermidis strains tested. Importantly, none of the PSM components were secreted by an agr mutant strain, indicating that PSM synthesis is regulated strictly by the agr quorum-sensing system. Furthermore, the agr mutant strain failed to elicit production of TNFalpha by human myeloid cells and induced significantly less neutrophil chemotaxis compared with the wild-type strain. Thus, quorum-sensing in S. epidermidis dramatically influenced activation of human host defence. We propose that an agr quorum-sensing mechanism facilitates growth and survival in infected hosts by adapting production of the pro-inflammatory PSMs to the stage of infection.

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Bacterial ToxinsChromatography, LiquidHumansInflammationMass SpectrometryMutationStaphylococcal InfectionsStaphylococcus epidermidisVirulenceComparative StudyJournal Article

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Cuong Vuong, Manuela Dürr, Aaron B Carmody, Andreas Peschel, Seymour J Klebanoff, Michael Otto. 2004. Regulated expression of pathogen-associated molecular pattern molecules in Staphylococcus epidermidis: quorum-sensing determines pro-inflammatory capacity and production of phenol-soluble modulins.. https://doi.org/10.1111/j.1462-5822.2004.00401.x

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