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Updated: May 22, 2026
08:03
A Tandem Liquid Chromatography–Mass Spectrometry-based Approach for Metabolite Analysis of Staphylococcus aureus
Published on: March 28, 2017
Single-cell approach dissecting agr quorum sensing dynamics in Staphylococcus aureus.
Julian Bär1, Mariane Pivard1, Samuel G V Charlton2
1Department of Infectious Diseases and Hospital Epidemiology, University Hospital Zürich, University of Zürich, Zürich, Switzerland.
Nature Communications
|May 20, 2026
Summary
Bacteria use quorum sensing (QS) to coordinate actions. This study reveals how different Staphylococcus aureus agr-types activate and interact at the single-cell level, uncovering complex signaling dynamics.
Area of Science:
- Microbiology
- Bacterial communication
- Systems biology
Background:
- Quorum sensing (QS) regulates bacterial collective behaviors via signaling molecules.
- The accessory gene regulator (agr) system in Staphylococcus aureus is a key QS virulence regulator.
- Understanding agr-type activation dynamics and cross-inhibition is crucial due to regulatory heterogeneity.
Purpose of the Study:
- To quantify agr-activation dynamics at single-cell resolution in Staphylococcus aureus.
- To investigate the activation sensitivities and cross-inhibition patterns among different agr-types.
- To explore the impact of genetic background and spatial interactions on agr-system behavior.
Main Methods:
- Utilized microfluidics and time-lapse microscopy for high-resolution imaging.
- Employed deep-learning-based image analysis to quantify agr-activation.
- Studied congenic and native agr-type strains, including cocultures.
Main Results:
- Observed significant differences in agr-type sensitivity to autoinducing peptides (AIPs), with agr-IV being highly sensitive and agr-III unresponsive.
- Frequently detected bimodal agr-activation distributions, indicating subpopulations with distinct activation behaviors.
- Demonstrated asymmetric cross-inhibition between agr-types (e.g., AIP-IV suppressed agr-I, but AIP-I did not inhibit agr-IV).
- Identified four distinct agr-interaction regimes in cocultures, influenced by agr-type pairing and genetic background.
Conclusions:
- Single-cell analysis reveals complex and heterogeneous agr-activation patterns in Staphylococcus aureus.
- Agr-type-specific signaling sensitivities and asymmetric cross-inhibition influence bacterial interactions and competition.
- This research provides a framework for linking single-cell QS dynamics to population-level outcomes and virulence.
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