Signalling-dependent interactions between the kinase-coupling protein CheW and chemoreceptors in living cells

Mol Microbiol. 2014 Sep;93(6):1144-55. doi: 10.1111/mmi.12727. Epub 2014 Aug 5.


Chemical signals sensed on the periplasmic side of bacterial cells by transmembrane chemoreceptors are transmitted to the flagellar motors via the histidine kinase CheA, which controls the phosphorylation level of the effector protein CheY. Chemoreceptor arrays comprise remarkably stable supramolecular structures in which thousands of chemoreceptors are networked through interactions between their cytoplasmic tips, CheA, and the small coupling protein CheW. To explore the conformational changes that occur within this protein assembly during signalling, we used in vivo cross-linking methods to detect close interactions between the coupling protein CheW and the serine receptor Tsr in intact Escherichia coli cells. We identified two signal-sensitive contacts between CheW and the cytoplasmic tip of Tsr. Our results suggest that ligand binding triggers changes in the receptor that alter its signalling contacts with CheW (and/or CheA).

Publication types

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

MeSH terms

  • Bacterial Proteins / metabolism
  • Binding Sites
  • Cysteine / metabolism
  • Escherichia coli / metabolism*
  • Escherichia coli Proteins / chemistry*
  • Escherichia coli Proteins / metabolism*
  • Histidine Kinase
  • Membrane Proteins / metabolism
  • Methyl-Accepting Chemotaxis Proteins
  • Models, Molecular
  • Protein Binding
  • Protein Structure, Secondary
  • Signal Transduction


  • Bacterial Proteins
  • CheW protein, E coli
  • Escherichia coli Proteins
  • Membrane Proteins
  • Methyl-Accepting Chemotaxis Proteins
  • cheY protein, E coli
  • tsr protein, E coli
  • Histidine Kinase
  • cheA protein, E coli
  • Cysteine