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Updated: Oct 1, 2025
06:08
Biophysical Characterization of Flagellar Motor Functions
Published on: January 18, 2017
8.4K
FliL ring enhances the function of periplasmic flagella.
Shuaiqi Guo1,2, Hui Xu3, Yunjie Chang1,2
1Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT 06536.
Summary
Researchers discovered how bacterial flagella proteins FliL, MotA, and MotB form a unique complex. This complex enhances motor function and bacterial motility in complex environments.
Area of Science:
- Microbiology
- Structural Biology
- Biophysics
Background:
- Bacterial flagella are essential for motility, enabling bacteria to navigate diverse environments.
- Understanding the structural basis of flagellar motor function is crucial for deciphering bacterial chemotaxis and pathogenesis.
Purpose of the Study:
- To elucidate the in situ structure of the flagellar motor complex in *Borrelia burgdorferi*.
- To investigate the role of flagellar proteins FliL, MotA, and MotB in motor assembly and function.
Main Methods:
- Cryo-electron tomography was employed to determine high-resolution structures of the flagellar motor.
- In situ structural analysis was performed on wild-type and mutant *Borrelia burgdorferi* cells.
Main Results:
- A unique supramolecular complex formed by FliL, MotA, and MotB was identified in situ.
- FliL was observed to enhance motor function by forming a ring around the MotA/MotB stator complex in its active conformation.
- FliL was found to facilitate the assembly of the stator complex around the flagellar motor.
Conclusions:
- The FliL-stator complex plays a critical role in regulating flagellar motor function and bacterial motility.
- Cooperative remodeling of the FliL-stator complex influences ion flux, optimizing motor performance in varied environments.
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