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Single-Cell Census of Mechanosensitive Channels in Living Bacteria
Bacteria are subjected to a host of different environmental stresses. One such insult occurs when cells encounter changes in the osmolarity of the surrounding media resulting in an osmotic shock. In recent years, a great deal has been learned about mechanosensitive (MS) channels which are thought to...
Autores principales: | , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Public Library of Science
2012
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3302805/ https://www.ncbi.nlm.nih.gov/pubmed/22427953 http://dx.doi.org/10.1371/journal.pone.0033077 |
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author | Bialecka-Fornal, Maja Lee, Heun Jin DeBerg, Hannah A. Gandhi, Chris S. Phillips, Rob |
author_facet | Bialecka-Fornal, Maja Lee, Heun Jin DeBerg, Hannah A. Gandhi, Chris S. Phillips, Rob |
author_sort | Bialecka-Fornal, Maja |
collection | PubMed |
description | Bacteria are subjected to a host of different environmental stresses. One such insult occurs when cells encounter changes in the osmolarity of the surrounding media resulting in an osmotic shock. In recent years, a great deal has been learned about mechanosensitive (MS) channels which are thought to provide osmoprotection in these circumstances by opening emergency release valves in response to membrane tension. However, even the most elementary physiological parameters such as the number of MS channels per cell, how MS channel expression levels influence the physiological response of the cells, and how this mean number of channels varies from cell to cell remain unanswered. In this paper, we make a detailed quantitative study of the expression of the mechanosensitive channel of large conductance (MscL) in different media and at various stages in the growth history of bacterial cultures. Using both quantitative fluorescence microscopy and quantitative Western blots our study complements earlier electrophysiology-based estimates and results in the following key insights: i) the mean number of channels per cell is much higher than previously estimated, ii) measurement of the single-cell distributions of such channels reveals marked variability from cell to cell and iii) the mean number of channels varies under different environmental conditions. The regulation of MscL expression displays rich behaviors that depend strongly on culturing conditions and stress factors, which may give clues to the physiological role of MscL. The number of stress-induced MscL channels and the associated variability have far reaching implications for the in vivo response of the channels and for modeling of this response. As shown by numerous biophysical models, both the number of such channels and their variability can impact many physiological processes including osmoprotection, channel gating probability, and channel clustering. |
format | Online Article Text |
id | pubmed-3302805 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2012 |
publisher | Public Library of Science |
record_format | MEDLINE/PubMed |
spelling | pubmed-33028052012-03-16 Single-Cell Census of Mechanosensitive Channels in Living Bacteria Bialecka-Fornal, Maja Lee, Heun Jin DeBerg, Hannah A. Gandhi, Chris S. Phillips, Rob PLoS One Research Article Bacteria are subjected to a host of different environmental stresses. One such insult occurs when cells encounter changes in the osmolarity of the surrounding media resulting in an osmotic shock. In recent years, a great deal has been learned about mechanosensitive (MS) channels which are thought to provide osmoprotection in these circumstances by opening emergency release valves in response to membrane tension. However, even the most elementary physiological parameters such as the number of MS channels per cell, how MS channel expression levels influence the physiological response of the cells, and how this mean number of channels varies from cell to cell remain unanswered. In this paper, we make a detailed quantitative study of the expression of the mechanosensitive channel of large conductance (MscL) in different media and at various stages in the growth history of bacterial cultures. Using both quantitative fluorescence microscopy and quantitative Western blots our study complements earlier electrophysiology-based estimates and results in the following key insights: i) the mean number of channels per cell is much higher than previously estimated, ii) measurement of the single-cell distributions of such channels reveals marked variability from cell to cell and iii) the mean number of channels varies under different environmental conditions. The regulation of MscL expression displays rich behaviors that depend strongly on culturing conditions and stress factors, which may give clues to the physiological role of MscL. The number of stress-induced MscL channels and the associated variability have far reaching implications for the in vivo response of the channels and for modeling of this response. As shown by numerous biophysical models, both the number of such channels and their variability can impact many physiological processes including osmoprotection, channel gating probability, and channel clustering. Public Library of Science 2012-03-13 /pmc/articles/PMC3302805/ /pubmed/22427953 http://dx.doi.org/10.1371/journal.pone.0033077 Text en Bialecka-Fornal et al. http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are properly credited. |
spellingShingle | Research Article Bialecka-Fornal, Maja Lee, Heun Jin DeBerg, Hannah A. Gandhi, Chris S. Phillips, Rob Single-Cell Census of Mechanosensitive Channels in Living Bacteria |
title | Single-Cell Census of Mechanosensitive Channels in Living Bacteria |
title_full | Single-Cell Census of Mechanosensitive Channels in Living Bacteria |
title_fullStr | Single-Cell Census of Mechanosensitive Channels in Living Bacteria |
title_full_unstemmed | Single-Cell Census of Mechanosensitive Channels in Living Bacteria |
title_short | Single-Cell Census of Mechanosensitive Channels in Living Bacteria |
title_sort | single-cell census of mechanosensitive channels in living bacteria |
topic | Research Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3302805/ https://www.ncbi.nlm.nih.gov/pubmed/22427953 http://dx.doi.org/10.1371/journal.pone.0033077 |
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