Cyclic di-GMP differentially tunes a bacterial flagellar motor through a novel class of CheY-like regulators

Elife. 2017 Nov 1:6:e28842. doi: 10.7554/eLife.28842.

Abstract

The flagellar motor is a sophisticated rotary machine facilitating locomotion and signal transduction. Owing to its important role in bacterial behavior, its assembly and activity are tightly regulated. For example, chemotaxis relies on a sensory pathway coupling chemical information to rotational bias of the motor through phosphorylation of the motor switch protein CheY. Using a chemical proteomics approach, we identified a novel family of CheY-like (Cle) proteins in Caulobacter crescentus, which tune flagellar activity in response to binding of the second messenger c-di-GMP to a C-terminal extension. In their c-di-GMP bound conformation Cle proteins interact with the flagellar switch to control motor activity. We show that individual Cle proteins have adopted discrete cellular functions by interfering with chemotaxis and by promoting rapid surface attachment of motile cells. This study broadens the regulatory versatility of bacterial motors and unfolds mechanisms that tie motor activity to mechanical cues and bacterial surface adaptation.

Keywords: Caulobacter crescentus; attachment; c-di-GMP; chemotaxis; flagellum; infectious disease; microbiology; motility.

Publication types

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

MeSH terms

  • Bacterial Adhesion*
  • Bacterial Proteins / metabolism*
  • Caulobacter crescentus / chemistry
  • Caulobacter crescentus / physiology*
  • Chemotaxis*
  • Cyclic GMP / analogs & derivatives*
  • Cyclic GMP / metabolism
  • Flagella / chemistry
  • Flagella / physiology*
  • Gene Expression Regulation, Bacterial*
  • Protein Binding
  • Proteome / analysis

Substances

  • Bacterial Proteins
  • Proteome
  • bis(3',5')-cyclic diguanylic acid
  • Cyclic GMP