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Effects of starvation on physiological activity and chlorine disinfection resistance in Escherichia coli O157:H7Escherichia coli O157:H7 can persist for days to weeks in microcosms simulating natural conditions. In this study, we used a suite of fluorescent, in situ stains and probes to assess the influence of starvation on physiological activity based on membrane potential (rhodamine 123 assay), membrane integrity (LIVE/DEAD BacLight kit), respiratory activity (5-cyano-2,3-di-4-tolyl-tetrazolium chloride assay), intracellular esterase activity (ScanRDI assay), and 16S rRNA content. Growth-dependent assays were also used to assess substrate responsiveness (direct viable count [DVC] assay), ATP activity (MicroStar assay), and culturability (R2A agar assay). In addition, resistance to chlorine disinfection was assessed. After 14 days of starvation, the DVC values decreased, while the values in all other assays remained relatively constant and equivalent to each other. Chlorine resistance progressively increased through the starvation period. After 29 days of starvation, there was no significant difference in chlorine resistance between control cultures that had not been exposed to the disinfectant and cultures that had been exposed. This study demonstrates that E. coli O157:H7 adapts to starvation conditions by developing a chlorine resistance phenotype.
Document ID
20040142158
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Lisle, J. T.
(Montana State University Bozeman, Montana 59717, United States)
Broadaway, S. C.
Prescott, A. M.
Pyle, B. H.
Fricker, C.
McFeters, G. A.
Date Acquired
August 22, 2013
Publication Date
December 1, 1998
Publication Information
Publication: Applied and environmental microbiology
Volume: 64
Issue: 12
ISSN: 0099-2240
Subject Category
Life Sciences (General)
Distribution Limits
Public
Copyright
Other
Keywords
NASA Discipline Environmental Health
Non-NASA Center

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