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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.
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.
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.
@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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