Reaction of N-acylhomoserine lactones with hydroxyl radicals: rates, products, and effects on signaling activity.

Published

Journal Article

Chemical communication in bacteria, sometimes called quorum sensing, is a fundamental microbial process that is based on the exchange of molecular signals between cells. The signaling molecules involved in this process are thermodynamically unstable in some environments and their degradation affects microbial communication. This work reports the oxidation of a series of substituted N-acylhomoserine lactones (AHLs, a class of quorum sensing signals) by hydroxyl radicals. The corresponding bimolecular rate constants were obtained and correlated positively with the length of the acyl side chain (C, in numbers of carbon atoms) ranging from 2.4 × 10(9) M(-1) s(-1) to 9.4 × 10(9) M(-1) s(-1) (C4- to C10-AHL), 2.4 × 10(8) M(-1) s(-1) for 3-oxo C6-AHL, and 2.94 × 10(9) M(-1) s(-1) for 3-oxo C8-AHL. Liquid chromatography-mass spectrometric techniques were applied to qualify the identity and quantify the yields of the hydroxyl radical oxidation products of C6-AHL (aldo, keto, and hydroxylated C6-analogues identified). The biological activity of C6-AHL and associated products was determined using the Vibrio harveyi bioluminescence bioassay. Oxidation resulted in a net increase in assay response indexed against the starting AHL. This result suggested that the application of HO• based technologies such as advanced oxidation processes for biofilm control may result in unintended quorum sensing responses by microbial communities.

Full Text

Duke Authors

Cited Authors

  • Frey, RL; He, L; Cui, Y; Decho, AW; Kawaguchi, T; Ferguson, PL; Ferry, JL

Published Date

  • October 2010

Published In

Volume / Issue

  • 44 / 19

Start / End Page

  • 7465 - 7469

PubMed ID

  • 20809590

Pubmed Central ID

  • 20809590

Electronic International Standard Serial Number (EISSN)

  • 1520-5851

International Standard Serial Number (ISSN)

  • 0013-936X

Digital Object Identifier (DOI)

  • 10.1021/es100663e

Language

  • eng