Determination of Acyl Homoserine Lactone and Tetramic Acid Concentrations in Biological Samples
Within environmental communities, there is a constant struggle for survival, as nutrients are often limited. In response, bacteria have developed elaborate methods to deal with competitors. One such mechanism is the coordination of behaviors and function via the exchange of small chemical signals in a process known as quorum sensing. This process is especially prominent in the pathogenicity of Pseudomonas aeruginosa, an opportunistic human pathogen that forms sessile communities known as biofilms. These biofilms play an important role in the lifestyle of P. aeruginosa, either in their natural environment or during establishment and maintenance of infection in human hosts; thus, they often have grievous effects on human health. As such, a method for the detection of these QS signals may provide insights into the pathogenicity and survival of P. aeruginosa. In this chapter, we present a method for the extraction and quantitation of the P. aeruginosa QS signal N-3-oxo-dodecanoyl-homoserine lactone, and its rearranged tetramic acid product, C12-TA, which itself has implications as a survival tactic used by P. aeruginosa.
Key wordsQuorum sensing Biofilm Pseudomonas aeruginosa Acyl homoserine lactone Tetramic acid
This work was supported by the National Institutes of Health (AI079503 to KDJ, AI080715 to GFK), the Skaggs Institute for Chemical Biology, and a Sanofi-Aventis Graduate Fellowship (CAL). We thank Prof. Barbara Iglewski for providing gfp-expressing P. aeruginosa and Dr. Victoria Wagner for helpful discussions. We would also like to thank Dr. Malcolm Wood and Dr. William Kiosses for assistance with microscopy experiments, as well as Dr. Gary Siuzdak and Bill Webb of the Scripps Center for Mass Spectrometry for assistance with the mass spectrometry experiments. This manuscript has been assigned TSRI manuscript #20556.
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