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Global genome response of Escherichia coli O157:H7 Sakai during dynamic changes in growth kinetics induced by an abrupt downshift in water activity
Citation
Kocharunchitt, C and King, T and Gobius, K and Bowman, JP and Ross, T, Global genome response of Escherichia coli O157:H7 Sakai during dynamic changes in growth kinetics induced by an abrupt downshift in water activity, PLoS One, 9, (3) Article e90422. ISSN 1932-6203 (2014) [Refereed Article]
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Copyright Statement
Copyright 2014 the Authors-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 credited
DOI: doi:10.1371/journal.pone.0090422
Abstract
The present study was undertaken to investigate growth kinetics and time-dependent change in global expression of
Escherichia coli O157:H7 Sakai upon an abrupt downshift in water activity (aw). Based on viable count data, shifting E. coli
from aw 0.993 to aw 0.985 or less caused an apparent loss, then recovery, of culturability. Exponential growth then resumed
at a rate characteristic for the aw imposed. To understand the responses of this pathogen to abrupt osmotic stress, we
employed an integrated genomic and proteomic approach to characterize its cellular response during exposure to a rapid
downshift but still within the growth range from aw 0.993 to aw 0.967. Of particular interest, genes and proteins with cell
envelope-related functions were induced during the initial loss and subsequent recovery of culturability. This implies that
cells undergo remodeling of their envelope composition, enabling them to adapt to osmotic stress. Growth at low aw,
however, involved up-regulating additional genes and proteins, which are involved in the biosynthesis of specific amino
acids, and carbohydrate catabolism and energy generation. This suggests their important role in facilitating growth under
such stress. Finally, we highlighted the ability of E. coli to activate multiple stress responses by transiently inducing the RpoE
and RpoH regulons to control protein misfolding, while simultaneously activating the master stress regulator RpoS to
mediate long-term adaptation to hyperosmolality. This investigation extends our understanding of the potential
mechanisms used by pathogenic E. coli to adapt, survive and grow under osmotic stress, which could potentially be
exploited to aid the selection and/or development of novel strategies to inactivate this pathogen.
Item Details
| Item Type: | Refereed Article |
|---|---|
| Research Division: | Biological Sciences |
| Research Group: | Microbiology |
| Research Field: | Bacteriology |
| Objective Division: | Expanding Knowledge |
| Objective Group: | Expanding knowledge |
| Objective Field: | Expanding knowledge in the biological sciences |
| UTAS Author: | Kocharunchitt, C (Dr Jay Kocharunchitt) |
| UTAS Author: | Bowman, JP (Associate Professor John Bowman) |
| UTAS Author: | Ross, T (Professor Tom Ross) |
| ID Code: | 89622 |
| Year Published: | 2014 |
| Web of Science® Times Cited: | 25 |
| Deposited By: | Tasmanian Institute of Agriculture |
| Deposited On: | 2014-03-10 |
| Last Modified: | 2017-11-06 |
| Downloads: | 396 View Download Statistics |
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