Kinetic constraints on acylated homoserine lactone-based quorum sensing in marine environments
MetadataShow full item record
KeywordQuorum sensing; Quorum quenching; Marine bacteria; Acylated homoserine lactone; HPLC; Mass spectrometry; Degradation
Quorum sensing (QS) via acylated homoserine lactones (AHLs) was discovered in the ocean, yet AHLs are expected to be very short-lived at seawater pH due to rapid abiotic degradation. Quorum quenching, the enzymatic degradation of AHLs, is also likely. To better understand the potential for QS to regulate behaviors of marine bacteria, we investigated the degradation of a variety of AHL molecules in several types of seawater media. We did this by incubating AHLs and tracking their concentration using HPLC/electrospray-ionization mass-spectrometry (HPLC/ESI-MS). AHL concentrations decreased with time, and degradation rate coefficients were calculated by applying a first-order rate law. The rate of abiotic degradation showed strong dependence on acyl chain length and the presence of 3-oxo substitutions on the acyl chain. We found that the rate of abiotic degradation of AHLs in artificial seawater was much slower than that predicted by an oft-cited equation for non-marine media that takes only pH into account. However, AHLs degraded more rapidly in natural seawater than in artificial seawater, an observation we found to be due to quorum quenching enzyme activity. By applying calculated degradation rates in a simple steady-state calculation, we suggest that despite the observed quorum quenching activity, AHLs are likely to be viable signals in organic particles and in other microbial ‘hotpsots’ in marine environments.
Author Posting. © Inter-Research, 2009. This article is posted here by permission of Inter-Research for personal use, not for redistribution. The definitive version was published in Aquatic Microbial Ecology 54 (2009): 127-133, doi:10.3354/ame01261.
Showing items related by title, author, creator and subject.
Evidence for quorum sensing and differential metabolite production by a marine bacterium in response to DMSP Johnson, Winifred M.; Kido Soule, Melissa C.; Kujawinski, Elizabeth B. (Nature Publishing Group, 2016-02-16)Microbes, the foundation of the marine foodweb, do not function in isolation, but rather rely on molecular level interactions among species to thrive. Although certain types of interactions between autotrophic and heterotrophic ...
A bacterial quorum-sensing precursor induces mortality in the marine coccolithophore, Emiliania huxleyi Harvey, Elizabeth L.; Deering, Robert W.; Rowley, David C.; El Gamal, Abrahim; Schorn, Michelle A.; Moore, Bradley S.; Johnson, Matthew D.; Mincer, Tracy J.; Whalen, Kristen E. (Frontiers Media, 2016-02-03)Interactions between phytoplankton and bacteria play a central role in mediating biogeochemical cycling and food web structure in the ocean. However, deciphering the chemical drivers of these interspecies interactions ...
The quorum-sensing regulation of Vibrio fischeri : novel components of the autoinducer/LuxR regulatory circuit Callahan, Sean M. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1999-06)In the marine bacterium Vibrio fischeri two intercellular homoserine-Iactone signal molecules (luxI-dependent 30C6-HSL and the ainS-dependent C8-HSL) and the transcriptional activator LuxR regulate the luminescence system ...