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Scalable Isolation and Purification of Extracellular Vesicles from Escherichia coli and Other Bacteria
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Computing the motor torque of Escherichia coli
1Department of Applied Mathematics and Theoretical Physics, Centre for Mathematical Sciences, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA, UK. e.lauga@damtp.cam.ac.uk.
Soft Matter
|June 14, 2018
Summary
Bacterial flagellar motors generate torque for cell locomotion. This study computes Escherichia coli motor torque, revealing a range of 440–829 pN nm, influenced by surface proximity.
Area of Science:
- Microbiology
- Biophysics
- Nanotechnology
Background:
- Bacteria utilize a rotary motor to power flagellar filaments for locomotion.
- Previous estimations of bacterial motor torque varied significantly.
Purpose of the Study:
- To compute the torque of the Escherichia coli rotary motor using validated numerical methods.
- To determine the torque range consistent with experimental observations of swimming and surface-attached cells.
Main Methods:
- Employed boundary integral methods for Stokes flow and a hybrid boundary element-slender body theory model.
- Modeled both the bacterial cell body and its helical flagellar filament.
Main Results:
- Calculated bacterial motor torque values ranging from 440 to 829 pN nm.
- Torque values were critically dependent on the distance between flagellar filaments and a nearby surface.
Conclusions:
- The study provides a refined estimation of bacterial rotary motor torque.
- Environmental factors, such as surface proximity, significantly impact motor torque output.
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