1. Microbiology and Infectious Disease
  2. Structural Biology and Molecular Biophysics

Structural insights into flagellar stator-rotor interactions

  1. Yunjie Chang
  2. Ki Hwan Moon
  3. Xiaowei Zhao
  4. Steven J Norris
  5. MD A Motaleb  Is a corresponding author
  6. Jun Liu  Is a corresponding author
  1. Yale University, United States
  2. East Carolina University, United States
  3. University of Texas Health Science Center at Houston, United States
https://doi.org/10.7554/eLife.48979
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  1. Yunjie Chang
  2. Ki Hwan Moon
  3. Xiaowei Zhao
  4. Steven J Norris
  5. MD A Motaleb
  6. Jun Liu
(2019)
Structural insights into flagellar stator-rotor interactions
eLife 8:e48979.
https://doi.org/10.7554/eLife.48979
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Abstract

The bacterial flagellar motor is a molecular machine that can rotate the flagellar filament at high speed. The rotation is generated by the stator-rotor interaction, coupled with an ion flux through the torque-generating stator. Here we employed cryo-electron tomography to visualize the intact flagellar motor in the Lyme disease spirochete, Borrelia burgdorferi. By analyzing the motor structures of wild-type and stator-deletion mutants, we not only localized the stator complex in situ, but also revealed the stator-rotor interaction at an unprecedented detail. Importantly, the stator-rotor interaction induces a conformational change in the flagella C-ring. Given our observation that a non-motile mutant, in which proton flux is blocked, cannot generate the similar conformational change, we propose that the proton-driven torque is responsible for the conformational change required for flagellar rotation.

Data availability

Data have been placed in the Electron Microscopy Data Bank under the accession numbers EMD-0534, EMD-0536, EMD-0537, and EMD-0538

The following data sets were generated

Article and author information

Author details

  1. Yunjie Chang

    Department of Microbial Pathogenesis, Yale University, New Haven, United States
    Competing interests
    The authors declare that no competing interests exist.

  2. Ki Hwan Moon

    Department of Microbiology and Immunology, East Carolina University, Greenville, United States
    Competing interests
    The authors declare that no competing interests exist.

  3. Xiaowei Zhao

    Department of Pathology and Laboratory Medicine, University of Texas Health Science Center at Houston, Houston, United States
    Competing interests
    The authors declare that no competing interests exist.

  4. Steven J Norris

    Department of Pathology and Laboratory Medicine, University of Texas Health Science Center at Houston, Houston, United States
    Competing interests
    The authors declare that no competing interests exist.

  5. MD A Motaleb

    Department of Microbiology and Immunology, East Carolina University, Greenville, United States
    For correspondence
    MOTALEBM@ecu.edu
    Competing interests
    The authors declare that no competing interests exist.

  6. Jun Liu

    Department of Microbial Pathogenesis, Yale University, West Haven, United States
    For correspondence
    jliu@yale.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3108-6735

Funding

National Institute of Allergy and Infectious Diseases (R01AI087946)

  • Jun Liu

National Institute of Allergy and Infectious Diseases (R01AI132818)

  • MD A Motaleb

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Copyright

© 2019, Chang 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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  1. Yunjie Chang
  2. Ki Hwan Moon
  3. Xiaowei Zhao
  4. Steven J Norris
  5. MD A Motaleb
  6. Jun Liu
(2019)
Structural insights into flagellar stator-rotor interactions
eLife 8:e48979.
https://doi.org/10.7554/eLife.48979

Share this article

https://doi.org/10.7554/eLife.48979

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