Dynamic domain arrangement of CheA-CheY complex regulates bacterial thermotaxis, as revealed by NMR

Sci Rep. 2017 Nov 28;7(1):16462. doi: 10.1038/s41598-017-16755-x.

Abstract

Bacteria utilize thermotaxis signal transduction proteins, including CheA, and CheY, to switch the direction of the cell movement. However, the thermally responsive machinery enabling warm-seeking behavior has not been identified. Here we examined the effects of temperature on the structure and dynamics of the full-length CheA and CheY complex, by NMR. Our studies revealed that the CheA-CheY complex exists in equilibrium between multiple states, including one state that is preferable for the autophosphorylation of CheA, and another state that is preferable for the phosphotransfer from CheA to CheY. With increasing temperature, the equilibrium shifts toward the latter state. The temperature-dependent population shift of the dynamic domain arrangement of the CheA-CheY complex induced changes in the concentrations of phosphorylated CheY that are comparable to those induced by chemical attractants or repellents. Therefore, the dynamic domain arrangement of the CheA-CheY complex functions as the primary thermally responsive machinery in warm-seeking behavior.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Escherichia coli / physiology*
  • Escherichia coli Proteins / chemistry*
  • Escherichia coli Proteins / metabolism
  • Histidine Kinase / chemistry*
  • Histidine Kinase / metabolism
  • Magnetic Resonance Spectroscopy*
  • Methyl-Accepting Chemotaxis Proteins / chemistry*
  • Methyl-Accepting Chemotaxis Proteins / metabolism
  • Models, Biological
  • Molecular Dynamics Simulation*
  • Multiprotein Complexes / chemistry
  • Multiprotein Complexes / metabolism
  • Protein Binding
  • Protein Conformation
  • Protein Interaction Domains and Motifs
  • Structure-Activity Relationship
  • Taxis Response*

Substances

  • Escherichia coli Proteins
  • Methyl-Accepting Chemotaxis Proteins
  • Multiprotein Complexes
  • cheY protein, E coli
  • Histidine Kinase
  • cheA protein, E coli