LasR Receptor for Detection of Long-Chain Quorum-Sensing Signals: Identification of N-Acyl-homoserine Lactones Encoded by the avsI Locus of Agrobacterium vitis
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Bacterial biosensor strains have greatly facilitated the rapid discovery, isolation, and study of quorum-sensing systems. In this study, we determined the relative sensitivity of a LasR-based E. coli bacterial bioluminescence biosensor JM109 (pSB1075) for 13 diverse long-chain N-acyl-homoserine lactones (AHLs) including oxygen-substituted and -unsubstituted AHLs containing 14, 16, and 18 carbons and with and without double bonds. Furthermore, we show by bioassay, HPLC, and GC/MS that four long-chain AHLs of the C16-HSL family are encoded by the avsI gene of Agrobacterium vitis strain F2/5, a non-tumorigenic strain that inhibits pathogenic strains of A. vitis from causing crown gall on grape. The four C16-HSLs include: C16-HSL, N-hexadecanoyl homoserine lactone; 3-oxo-C16-HSL, N-(3-oxohexadecanoyl)homoserine lactone; C16:1-HSL, N-(cis-9-octadecenoyl)homoserine lactone; and 3-oxo-C16:1-HSL, N-(3-oxo-cis-11-hexadecenoyl)homoserine lactone. Thus, the LasR-based bioluminescent biosensor tested in this study should serve as a useful tool for the detection of various long-chain AHLs with and without double bonds as well as those oxylated at the third carbon from uninvestigated species.
KeywordsHigh Pressure Liquid Chromatography Quorum Sense Homoserine Homoserine Lactone Acyl Side Chain
M. A. Savka thanks Rochester Institute of Technology (RIT) for a sabbatical leave of absence. This study was supported by the NRI Competitive Grants Program/USDA award numbers 2002-35319-12577 to M. A. Savka and 2006-35319-16558 to T. J .Burr.
- 4.Eberhard A, Schineller JB (2000) Chemical synthesis of bacterial autoinducers and analogs. In: Ziegler MM, Baldwin TO (eds) Methods in enzymology, vol 305. Academic Press, New York, pp 301–315Google Scholar
- 6.Fuqua C, Winans S (1999) Signal generation in autoinduction systems: synthesis of acylated homoserine lactones by LuxI-type proteins. In: Dunny GM, Winans SC (eds) Cell-cell signaling in bacteria. ASM Press, Washington, DC, pp 211–230Google Scholar
- 16.Li Y, Gronquist MR, Hao G, Holden MR, Eberhard A, Scott RA, Savka MA, Szegedi E, Sule S et al (2006) Chromosome and plasmid-encoded N-acyl-homoserine lactones produced by Agrobacterium vitis wild type and mutants that differ in their interactions with grape and tobacco. Physiol Mol Plant Pathol 67:284–290CrossRefGoogle Scholar
- 22.McLafferty FW (1966) Interpretation of mass spectra an introduction. W. A. Benjamin, ReadingGoogle Scholar
- 24.Ortori CA, Atkinson S, Chhabra SR, Camara M, Williams P, Barrett DA (2006) Comprehensive profiling of N-acylhomoserine lactones produced by Yersinia pseudotuberculosis using liquid chromatography coupled to hybrid quadrupole-linear ion trap mass spectrometry. Anal Bioanal Chem 387:497–511CrossRefPubMedGoogle Scholar