Deducing receptor signaling parameters from in vivo analysis: LuxN/AI-1 quorum sensing in Vibrio harveyi

Cell. 2008 Aug 8;134(3):461-73. doi: 10.1016/j.cell.2008.06.023.

Abstract

Quorum sensing, a process of bacterial cell-cell communication, relies on production, detection, and response to autoinducer signaling molecules. LuxN, a nine-transmembrane domain protein from Vibrio harveyi, is the founding example of membrane-bound receptors for acyl-homoserine lactone (AHL) autoinducers. We used mutagenesis and suppressor analyses to identify the AHL-binding domain of LuxN and discovered LuxN mutants that confer both decreased and increased AHL sensitivity. Our analysis of dose-response curves of multiple LuxN mutants pins these inverse phenotypes on quantifiable opposing shifts in the free-energy bias of LuxN for occupying its kinase and phosphatase states. To understand receptor activation and to characterize the pathway signaling parameters, we exploited a strong LuxN antagonist, one of fifteen small-molecule antagonists we identified. We find that quorum-sensing-mediated communication can be manipulated positively and negatively to control bacterial behavior and, more broadly, that signaling parameters can be deduced from in vivo data.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • 4-Butyrolactone / analogs & derivatives*
  • 4-Butyrolactone / metabolism
  • Acyl-Butyrolactones / metabolism
  • Amino Acid Sequence
  • Bacterial Proteins / antagonists & inhibitors
  • Bacterial Proteins / chemistry*
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism*
  • Molecular Sequence Data
  • Mutagenesis, Site-Directed
  • Protein Kinases / chemistry*
  • Protein Kinases / genetics
  • Protein Kinases / metabolism*
  • Protein Structure, Tertiary
  • Quorum Sensing*
  • Transcription Factors / antagonists & inhibitors
  • Transcription Factors / chemistry*
  • Transcription Factors / genetics
  • Transcription Factors / metabolism*
  • Vibrio / chemistry*
  • Vibrio / metabolism*

Substances

  • Acyl-Butyrolactones
  • Bacterial Proteins
  • Transcription Factors
  • N-(3-oxohexanoyl)-3-aminodihydro-2(3H)-furanone
  • Protein Kinases
  • luxN protein, Vibrio harveyi
  • 4-Butyrolactone