Structural insights into flagellar stator-rotor interactions
- Yale University, United States
- East Carolina University, United States
- University of Texas Health Science Center at Houston, United States
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
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Asymmetric reconstruction of the in situ flagellar motor structure in Borrelia burgdorferiElectron Microscopy Data Bank, EMD-0534.
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Local refinement of stator-rotor interaction region in flagellar motor of wild type Borrelia burgdorferiElectron Microscopy Data Bank, EMD-0536.
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cryo-ET flagellar motor structure of motB deletion Borrelia burgdorferiElectron Microscopy Data Bank, EMD-0537.
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Local refinement for the in-situ flagellar motor structure of motB deletion Borrelia burgdorferiElectron Microscopy Data Bank, EMD-0538.
Article and author information
Author details
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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