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In vitro screens for quorum sensing inhibitors and in vivo confirmation of their effect

Nature Protocols volume 5, pages 282293 (2010) | Download Citation


This article will introduce the reader to protocols intended for (i) identification of quorum sensing (QS) inhibitors (QSIs), (ii) characterization of these compounds in vitro and (iii) evaluation of these compounds in animal models. Traditional antimicrobial drugs are designed against planktonic bacteria and not against bacterial biofilms. In biofilms, bacteria are highly resistant to otherwise lethal treatments and they communicate with each other, thus enabling coordinated group behavior. For many years, we have focused on interference with cell to cell communication, also known as QS, with the aim of disabling the expression of virulence and reduction of antibiotic tolerance. Here we present protocols for screening and testing for acyl-homoserine lactone (AHL)-dependent QS inhibition. We also present protocols for the in vivo validation of QSIs as possible drug candidates. The presented methods allow the evaluation of QS inhibition by a potential drug candidate within 2–3 weeks.

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We thank Anne Kirstine Nielsen for her contribution to experimental setups.

Author information


  1. Department of International Health, Immunology and Microbiology, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark.

    • Thomas Bjarnsholt
    • , Maria van Gennip
    • , Tim H Jakobsen
    • , Louise D Christensen
    •  & Michael Givskov
  2. Department of Clinical Microbiology, Rigshospitalet, Copenhagen, Denmark.

    • Thomas Bjarnsholt
    •  & Peter Ø Jensen


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All authors contributed extensively to developing and writing the protocols presented in this paper.

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Correspondence to Michael Givskov.

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