Cyclic di-GMP differentially tunes a bacterial flagellar motor through a novel class of CheY-like regulators
- University of Basel, Switzerland
- Yale University, United States
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.
Article and author information
Author details
Funding
European Research Council (Advanced Research Grant to U.J.)
- Urs Jenal
Paul G. Allen Family Foundation (award no. 11562)
- Thierry Emonet
Swiss National Science Foundation (Sinergia grant CRSII3_127433)
- Urs Jenal
National Institutes of Health (grant no. 1R01GM106189)
- Thierry Emonet
Swiss National Science Foundation (grant 31003A_166652)
- Tilman Schirmer
Swiss National Science Foundation (grant 31003A_173089)
- Stephan Grzesiek
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2017, Nesper et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Cyclic di-GMP differentially tunes a bacterial flagellar motor through a novel class of CheY-like regulators
eLife 6:e28842.
https://doi.org/10.7554/eLife.28842
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