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Updated: May 25, 2026

Biophysical Characterization of Flagellar Motor Functions

Biophysical Characterization of Flagellar Motor Functions

Published on: January 18, 2017

Forces and torques on rotating spirochete flagella.

Jing Yang¹, Greg Huber, Charles W Wolgemuth

¹Department of Cell Biology and Center for Cell Analysis and Modeling, University of Connecticut Health Center, Farmington, Connecticut 06030-6406, USA.

Physical Review Letters

|January 17, 2012

Summary

This summary is machine-generated.

Spirochetes like Borrelia burgdorferi swim using flagella in the periplasm. Our analysis suggests a fluid layer lubricates flagella, enabling efficient bacterial motility.

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Magnetic Tweezers for the Measurement of Twist and Torque

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Area of Science:

Microbiology
Biophysics
Bacterial Motility

Background:

Spirochetes are motile bacteria with unique helical shapes and periplasmic flagella.
In Borrelia burgdorferi, flagellar rotation causes cellular undulations for swimming.
The mechanics of flagella-cell body interaction and resistive forces remain unclear.

Purpose of the Study:

To investigate the forces and torques between flagella and the cell body in spirochetes.
To determine the nature of resistive forces (friction vs. fluid drag) acting on periplasmic flagella.
To analyze the motion of an elastic flagellum within the periplasm.

Main Methods:

Mathematical modeling of an elastic flagellum rotating in a confined space.
Analysis of fluid dynamics and resistive forces in the periplasm.
Calculation of drag coefficients for flagellar rotation and sliding.

Main Results:

The study indicates that spirochetal flagella are likely separated from the cell wall by a lubricating fluid layer.
This fluid layer minimizes friction between the flagella and the cell wall.
Drag coefficients for flagellar rotation and sliding within the periplasm were determined.

Conclusions:

A lubricating fluid layer is crucial for efficient spirochetal motility.
Understanding periplasmic flagellar mechanics provides insights into bacterial locomotion.
This research contributes to the biophysical understanding of bacterial movement.