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Title: Flagella bending affects macroscopic properties of bacterial suspensions

Abstract

To survive in harsh conditions, motile bacteria swim in complex environments and respond to the surrounding flow. Here, we develop a mathematical model describing how flagella bending affects macroscopic properties of bacterial suspensions. First, we show how the flagella bending contributes to the decrease in the effective viscosity observed in dilute suspension. Our results do not impose tumbling (random reorientation) as was previously done to explain the viscosity reduction. Second, we demonstrate how a bacterium escapes from wall entrapment due to the self-induced buckling of flagella. Our results shed light on the role of flexible bacterial flagella in interactions of bacteria with shear flow and walls or obstacles.

Authors:
; ; ; ORCiD logo
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1366714
DOE Contract Number:
AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: Interface; Journal Volume: 14; Journal Issue: 130
Country of Publication:
United States
Language:
English

Citation Formats

Potomkin, M., Tournus, M., Berlyand, L. V., and Aranson, I. S. Flagella bending affects macroscopic properties of bacterial suspensions. United States: N. p., 2017. Web. doi:10.1098/rsif.2016.1031.
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Potomkin, M., Tournus, M., Berlyand, L. V., & Aranson, I. S. Flagella bending affects macroscopic properties of bacterial suspensions. United States. doi:10.1098/rsif.2016.1031.
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Potomkin, M., Tournus, M., Berlyand, L. V., and Aranson, I. S. Mon . "Flagella bending affects macroscopic properties of bacterial suspensions". United States. doi:10.1098/rsif.2016.1031.
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@article{osti_1366714,
title = {Flagella bending affects macroscopic properties of bacterial suspensions},
author = {Potomkin, M. and Tournus, M. and Berlyand, L. V. and Aranson, I. S.},
abstractNote = {To survive in harsh conditions, motile bacteria swim in complex environments and respond to the surrounding flow. Here, we develop a mathematical model describing how flagella bending affects macroscopic properties of bacterial suspensions. First, we show how the flagella bending contributes to the decrease in the effective viscosity observed in dilute suspension. Our results do not impose tumbling (random reorientation) as was previously done to explain the viscosity reduction. Second, we demonstrate how a bacterium escapes from wall entrapment due to the self-induced buckling of flagella. Our results shed light on the role of flexible bacterial flagella in interactions of bacteria with shear flow and walls or obstacles.},
doi = {10.1098/rsif.2016.1031},
journal = {Interface},
number = 130,
volume = 14,
place = {United States},
year = {Mon May 01 00:00:00 EDT 2017},
month = {Mon May 01 00:00:00 EDT 2017}
}
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Journal Article:
DOI:  10.1098/rsif.2016.1031
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  • ; ; - Biochemical and Biophysical Research Communications
    Inspired by recent interest in torsion of the central pair microtubules in eukaryotic flagella, a novel thin-walled elastic beam model is suggested to study critical condition under which uniform bending of a flagellum will cause lateral/torsional buckling of the central pair. The model is directed to the central pair itself and the role of all surrounding cross-linkings inside the flagellum is modeled as an equivalent surrounding elastic medium. The model predicts that bending-driven torsion of the central pair does occur when the radius of curvature of the bent flagellum reduces to a moderate critical value typically of tens of microns.more » In particular, this critical value is almost independent of the flagellum length, and more sensitive to the parameters defining the surrounding elastic medium than the shear modulus of microtubules. The predicted wavelengths of the torsional buckling mode are insensitive to the flagellum length and comparable to some known related experimental data. These results indicate that torsion of the central pair microtubules in flagella is inevitable as a result of bending-driven lateral buckling. This offers an entirely new insight into the ongoing research on the mechanism of the central pair torsion.« less

  • ; ; ; ... - Proc Natl Acad Sci USA
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  • ; ; ; ... - Interface
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  • ; ; ; ... - New Journal of Physics

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