Octanoyl-Homoserine Lactone Is the Cognate Signal for Burkholderia mallei BmaR1-BmaI1 Quorum Sensing
- 15 July 2007
- journal article
- Published by American Society for Microbiology in Journal of Bacteriology
- Vol. 189 (14), 5034-5040
- https://doi.org/10.1128/jb.00317-07
Abstract
Acyl-homoserine lactones (HSLs) serve as quorum-sensing signals for many Proteobacteria . Members of the LuxI family of signal generators catalyze the production of acyl-HSLs, which bind to a cognate receptor in the LuxR family of transcription factors. The obligate animal pathogen Burkholderia mallei produces several acyl-HSLs, and the B. mallei genome has four luxR and two luxI homologs, each of which has been established as a virulence factor. To begin to delineate the relevant acyl-HSL signals for B. mallei LuxR homologs, we analyzed the BmaR1-BmaI1 system. A comparison of acyl-HSL profiles from B. mallei ATCC 23344 and a B. mallei bmaI1 mutant indicates that octanoyl-HSL synthesis is BmaI1 dependent. Furthermore, octanoyl-HSL is the predominant acyl-HSL produced by BmaI1 in recombinant Escherichia coli . The synthesis of soluble BmaR1 in recombinant E. coli requires octanoyl-HSL or decanoyl-HSL. Insoluble aggregates of BmaR1 are produced in the presence of other acyl-HSLs and in the absence of acyl-HSLs. The bmaI1 promoter is activated by BmaR1 and octanoyl-HSL, and a 20-bp inverted repeat in the bmaI1 promoter is required for bmaI1 activation. Purified BmaR1 binds to this promoter region. These findings implicate octanoyl-HSL as the signal for BmaR1-BmaI1 quorum sensing and show that octanoyl-HSL and BmaR1 activate bmaI1 transcription.Keywords
This publication has 42 references indexed in Scilit:
- Quorum sensing regulates dpsA and the oxidative stress response in Burkholderia pseudomalleiMicrobiology, 2006
- The multifarious, multireplicon Burkholderia cepacia complexNature Reviews Microbiology, 2005
- Reversible Acyl-Homoserine Lactone Binding to Purified Vibrio fischeri LuxR ProteinJournal of Bacteriology, 2004
- Agrobacterium Bioassay Strain for Ultrasensitive Detection of N -Acylhomoserine Lactone-Type Quorum-Sensing Molecules: Detection of Autoinducers in Mesorhizobium huakuiiApplied and Environmental Microbiology, 2003
- A LuxR Homolog Controls Production of Symbiotically Active Extracellular Polysaccharide II by Sinorhizobium melilotiJournal of Bacteriology, 2002
- Listening in on bacteria: acyl-homoserine lactone signallingNature Reviews Molecular Cell Biology, 2002
- Quorum-sensing in Gram-negative bacteriaFEMS Microbiology Reviews, 2001
- CENSUS AND CONSENSUS IN BACTERIAL ECOSYSTEMS: The LuxR-LuxI Family of Quorum-Sensing Transcriptional RegulatorsAnnual Review of Microbiology, 1996
- Agrobacterium conjugation and gene regulation by N-acyl-L-homoserine lactonesNature, 1993
- R Factor Transfer in Rhizobium leguminosarumMicrobiology, 1974