A hierarchical quorum-sensing system in Yersinia pseudotuberculosis is involved in the regulation of motility and clumping

Mol Microbiol. 1999 Sep;33(6):1267-77. doi: 10.1046/j.1365-2958.1999.01578.x.


In cell-free Yersinia pseudotuberculosis culture supernatants, we have chemically characterized three N-acyl homoserine lactone (AHL) molecules, N-octanoyl homoserine lactone (C8-HSL), N-(3-oxohexanoyl)homoserine lactone (3-oxo-C6-HSL) and N-hexanoyl homoserine lactone (C6-HSL). We have identified, cloned and sequenced two pairs of LuxR/I homologues termed YpsR/I and YtbR/I. In Escherichia coli at 37 degrees C, YpsI and YtbI both synthesize C6-HSL, although YpsI is responsible for 3-oxo-C6-HSL and YtbI for C8-HSL synthesis respectively. However, in a Y. pseudotuberculosis ypsI-negative background, YtbI appears capable of adjusting the AHL profile from all three AHLs at 37 degrees C and 22 degrees C to the absence of 3-oxo-C6-HSL at 28 degrees C. Insertion deletion mutagenesis of ypsR leads to the loss of C8-HSL at 22 degrees C, which suggests that at this temperature the YpsR protein is involved in the hierarchical regulation of the ytbR/I locus. When compared with the parent strain, the ypsR and ypsI mutants exhibit a number of phenotypes, including clumping (ypsR mutant), overexpression of a major flagellin subunit (ypsR mutant) and increased motility (both ypsR and ypsI mutants). The clumping and motility phenotypes are both temperature dependent. These data are consistent with a hierarchical quorum-sensing cascade in Y. pseudotuberculosis that is involved in the regulation of clumping and motility.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 4-Butyrolactone / analogs & derivatives
  • 4-Butyrolactone / metabolism
  • Amino Acid Sequence
  • Bacterial Adhesion
  • Bacterial Proteins / genetics
  • Base Sequence
  • Cell Communication
  • DNA Primers / genetics
  • Escherichia coli / genetics
  • Genes, Bacterial
  • Molecular Sequence Data
  • Movement
  • Mutation
  • Phenotype
  • Repressor Proteins / genetics
  • Sequence Homology, Amino Acid
  • Trans-Activators / genetics
  • Yersinia pseudotuberculosis / genetics
  • Yersinia pseudotuberculosis / physiology*


  • Bacterial Proteins
  • DNA Primers
  • Repressor Proteins
  • Trans-Activators
  • luxL protein, Vibrio harveyi
  • LuxR autoinducer binding proteins
  • homoserine lactone
  • 4-Butyrolactone

Associated data

  • GENBANK/AF079136