Quorum Sensing pp 159-171 | Cite as

Defining the Structure and Function of Acyl-Homoserine Lactone Autoinducers

  • Mair E. A. ChurchillEmail author
  • Hiruy M. Sibhatu
  • Charis L. Uhlson
Part of the Methods in Molecular Biology book series (MIMB, volume 692)


Quorum sensing plays a central role in regulating many community-derived symbiotic and pathogenic relationships of bacteria, and as such has attracted much attention in recent years. Acyl-homoserine lactones (AHLs) are important signaling molecules in the quorum sensing gene-regulatory processes found in numerous gram-negative species of bacteria that interact with eukaryotic organisms. AHLs are produced by acyl-homoserine lactone synthases. Bacteria can have multiple genes for AHL synthase enzymes, and such species are likely to produce several different types of AHLs. Determination of the types and the relative amounts of AHLs produced by AHL synthases in bacteria under varied conditions provides important insights into the mechanism of AHL synthase function and the regulation of transcriptional cascades initiated by quorum sensing signaling. This chapter describes a mass spectrometry method for determining the types and relative amounts of AHLs present in a sample.

Key words

Acyl-homoserine lactone AHL Quorum sensing Mass spectrometry AHL synthase 



The authors would like to thank Drs. Ty Gould and Robert C. Murphy for their contributions in initially developing this method, Dr. Jake Herman for help in refining the method, and Dr. Joseph Hankin, Chris Johnson, and Wesley Martin for their assistance with the mass spectrometry. We also thank Dr. Robert C. Murphy for helpful suggestions and for use of the mass spectrometry equipment, which is supported by the Lipid Maps Large Scale Collaborative Grant (NIH GM069338 to R.C.M.). This work was supported by Grants from the National Science Foundation #0703467 and #0821220.


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Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  • Mair E. A. Churchill
    • 1
    Email author
  • Hiruy M. Sibhatu
    • 1
  • Charis L. Uhlson
    • 1
  1. 1.Department of PharmacologyUniversity of Colorado Denver School of MedicineAuroraUSA

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