Isolation of agr Quorum Sensing Autoinducers

  • Naomi Balaban
Part of the Methods in Molecular Biology book series (MIMB, volume 692)


Autoregulation of genes is often associated with quorum sensing systems where bacteria produce and secrete molecules that allow the cells to communicate with one another, leading to the activation of certain genes at certain population densities. Here we describe the identification of the agr as a quorum sensing system in Staphylococcus aureus and the isolation of agr autoinducers and inhibitors by northern blotting, real-time RT-PCR, and β-lactamase reporter cells assays.

Key words

Quorum sensing Autoinduction β-Lactamase reporter cell assay Temporal regulation RNAIII Agr Staphylococcus aureus 


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Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  • Naomi Balaban
    • 1
  1. 1.Department of Biomedical Sciences, Cummings School of Veterinary MedicineTufts UniversityNorth GraftonUSA

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