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Mechanics of biofilms formed of bacteria with fimbriae appendages
Gram-negative bacteria, as well as some Gram-positive bacteria, possess hair-like appendages known as fimbriae, which play an important role in adhesion of the bacteria to surfaces or to other bacteria. Unlike the sex pili or flagellum, the fimbriae are quite numerous, with of order 1000 fimbriae ap...
Autores principales: | , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
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Public Library of Science
2020
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7723297/ https://www.ncbi.nlm.nih.gov/pubmed/33290393 http://dx.doi.org/10.1371/journal.pone.0243280 |
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author | Jin, Xing Marshall, Jeffrey S. |
author_facet | Jin, Xing Marshall, Jeffrey S. |
author_sort | Jin, Xing |
collection | PubMed |
description | Gram-negative bacteria, as well as some Gram-positive bacteria, possess hair-like appendages known as fimbriae, which play an important role in adhesion of the bacteria to surfaces or to other bacteria. Unlike the sex pili or flagellum, the fimbriae are quite numerous, with of order 1000 fimbriae appendages per bacterial cell. In this paper, a recently developed hybrid model for bacterial biofilms is used to examine the role of fimbriae tension force on the mechanics of bacterial biofilms. Each bacterial cell is represented in this model by a spherocylindrical particle, which interact with each other through collision, adhesion, lubrication force, and fimbrial force. The bacterial cells absorb water and nutrients and produce extracellular polymeric substance (EPS). The flow of water and EPS, and nutrient diffusion within these substances, is computed using a continuum model that accounts for important effects such as osmotic pressure gradient, drag force on the bacterial cells, and viscous shear. The fimbrial force is modeled using an outer spherocylinder capsule around each cell, which can transmit tensile forces to neighboring cells with which the fimbriae capsule collides. We find that the biofilm structure during the growth process is dominated by a balance between outward drag force on the cells due to the EPS flow away from the bacterial colony and the inward tensile fimbrial force acting on chains of cells connected by adhesive fimbriae appendages. The fimbrial force also introduces a large rotational motion of the cells and disrupts cell alignment caused by viscous torque imposed by the EPS flow. The current paper characterizes the competing effects of EPS drag and fimbrial force using a series of computations with different values of the ratio of EPS to bacterial cell production rate and different numbers of fimbriae per cell. |
format | Online Article Text |
id | pubmed-7723297 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2020 |
publisher | Public Library of Science |
record_format | MEDLINE/PubMed |
spelling | pubmed-77232972020-12-16 Mechanics of biofilms formed of bacteria with fimbriae appendages Jin, Xing Marshall, Jeffrey S. PLoS One Research Article Gram-negative bacteria, as well as some Gram-positive bacteria, possess hair-like appendages known as fimbriae, which play an important role in adhesion of the bacteria to surfaces or to other bacteria. Unlike the sex pili or flagellum, the fimbriae are quite numerous, with of order 1000 fimbriae appendages per bacterial cell. In this paper, a recently developed hybrid model for bacterial biofilms is used to examine the role of fimbriae tension force on the mechanics of bacterial biofilms. Each bacterial cell is represented in this model by a spherocylindrical particle, which interact with each other through collision, adhesion, lubrication force, and fimbrial force. The bacterial cells absorb water and nutrients and produce extracellular polymeric substance (EPS). The flow of water and EPS, and nutrient diffusion within these substances, is computed using a continuum model that accounts for important effects such as osmotic pressure gradient, drag force on the bacterial cells, and viscous shear. The fimbrial force is modeled using an outer spherocylinder capsule around each cell, which can transmit tensile forces to neighboring cells with which the fimbriae capsule collides. We find that the biofilm structure during the growth process is dominated by a balance between outward drag force on the cells due to the EPS flow away from the bacterial colony and the inward tensile fimbrial force acting on chains of cells connected by adhesive fimbriae appendages. The fimbrial force also introduces a large rotational motion of the cells and disrupts cell alignment caused by viscous torque imposed by the EPS flow. The current paper characterizes the competing effects of EPS drag and fimbrial force using a series of computations with different values of the ratio of EPS to bacterial cell production rate and different numbers of fimbriae per cell. Public Library of Science 2020-12-08 /pmc/articles/PMC7723297/ /pubmed/33290393 http://dx.doi.org/10.1371/journal.pone.0243280 Text en © 2020 Jin, Marshall http://creativecommons.org/licenses/by/4.0/ This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/) , which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. |
spellingShingle | Research Article Jin, Xing Marshall, Jeffrey S. Mechanics of biofilms formed of bacteria with fimbriae appendages |
title | Mechanics of biofilms formed of bacteria with fimbriae appendages |
title_full | Mechanics of biofilms formed of bacteria with fimbriae appendages |
title_fullStr | Mechanics of biofilms formed of bacteria with fimbriae appendages |
title_full_unstemmed | Mechanics of biofilms formed of bacteria with fimbriae appendages |
title_short | Mechanics of biofilms formed of bacteria with fimbriae appendages |
title_sort | mechanics of biofilms formed of bacteria with fimbriae appendages |
topic | Research Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7723297/ https://www.ncbi.nlm.nih.gov/pubmed/33290393 http://dx.doi.org/10.1371/journal.pone.0243280 |
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