“Hot Stuff”: The Many Uses of a Radiolabel Assay in Detecting Acyl-Homoserine Lactone Quorum-Sensing Signals

Part of the Methods in Molecular Biology book series (MIMB, volume 1673)


Many Proteobacteria synthesize acyl-homoserine lactone (AHL) molecules for use as signals in cell density-dependent gene regulation known as quorum sensing (QS) and response. AHL detection protocols are essential to QS researchers and several techniques are available, including a 14C-AHL radiolabel assay. This assay is based on the uptake of radiolabeled methionine by living cells and conversion of the radiolabel into S-adenosylmethionine (SAM). The radiolabeled SAM is then incorporated into AHL signal by an AHL synthase enzyme. Here we describe a methodology to perform the AHL radiolabel assay, which is unbiased, relatively fast, and very sensitive compared to other AHL detection protocols.

Key words

14C-carboxy-methionine Quorum sensing QS LuxI Acyl-homoserine lactone AHL Acyl-HSL 



This work was sponsored by the following funding sources: (1) the Agricultural and Food Research Initiative Competitive Grants Program 2010-65108-20536 from the US Department of Agriculture, (2) the US Army Research Office Grant W911NF0910350, (3) the US Public Health Service (USPHS) Grant GM59026, and (4) the Genomic Science Program, US Department of Energy, Office of Science, Biological and Environmental Research, as part of the Plant Microbe Interfaces Scientific Focus Area ( Oak Ridge National Laboratory is managed by UT-Battelle LLC, for the US Department of Energy under contract DE-AC05-00OR22725.


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© Springer Science+Business Media LLC 2018

Authors and Affiliations

  1. 1.Department of MicrobiologyUniversity of WashingtonSeattleUSA

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