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Quorum Sensing pp 207-217 | Cite as

Quantifying Pseudomonas aeruginosa Quinolones and Examining Their Interactions with Lipids

  • Gregory C. Palmer
  • Jeffrey W. Schertzer
  • Lauren Mashburn-Warren
  • Marvin WhiteleyEmail author
Protocol
Part of the Methods in Molecular Biology book series (MIMB, volume 692)

Abstract

Pseudomonas aeruginosa produces a quorum sensing molecule termed the Pseudomonas Quinolone Signal (2-heptyl-3-hydroxy-4-quinolone; PQS) that regulates an array of genes involved in virulence. This chapter addresses four related techniques useful for detecting and quantifying PQS. First, extraction of PQS from complex mixtures (e.g. cell cultures) is described. Separation of PQS from extracts by Thin-Layer Chromatography (TLC) is used in combination with the natural fluorescence of the molecule for quantification. A second separation technique for the PQS precursor HHQ using High-Performance Liquid Chromatography (HPLC) is also described, and this assay exploits the molecule’s characteristic absorbance for quantification. A third method for quantification of PQS from simple mixtures (e.g. enzyme assays) using fluorescence is outlined. Finally, a protocol for determining PQS interactions with membrane lipids through Fluorescence Resonance Energy Transfer (FRET) is presented. These techniques allow for quantification and characterization of PQS from diverse environments, a prerequisite to understanding the biological functions of QS molecules.

Key words

Pseudomonas quinolone signal Thin-layer chromatography High-pressure liquid chromatography Fluorescence resonance energy transfer 

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Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  • Gregory C. Palmer
    • 1
  • Jeffrey W. Schertzer
    • 1
  • Lauren Mashburn-Warren
    • 1
  • Marvin Whiteley
    • 1
    Email author
  1. 1.Section of Molecular Genetics and MicrobiologyThe University of Texas at AustinAustinUSA

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