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08:16
Detection of Live Escherichia coli O157:H7 Cells by PMA-qPCR
Published on: February 1, 2014
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Isolation and Characterization of a Coliphage Specific for Escherichia coli 0157:H7
1Food Research Institute, University of Wisconsin-Madison, Madison, Wisconsin 53706.
Journal of Food Protection
|April 27, 2019
Summary
Researchers isolated a specific bacteriophage, AR1, from dairy farm manure that targets enterohemorrhagic Escherichia coli O157:H7. This coliphage shows potential for detecting E. coli O157:H7 and similar toxin-producing bacteria in various samples.
Area of Science:
- Microbiology
- Virology
- Food Safety
Background:
- Enterohemorrhagic Escherichia coli O157:H7 is a significant foodborne pathogen harbored by cattle.
- This bacterium causes severe gastrointestinal illness and hemolytic uremic syndrome in humans.
Purpose of the Study:
- To investigate the presence of E. coli O157:H7 and specific bacteriophages in cattle manure.
- To characterize a newly isolated bacteriophage with potential diagnostic applications.
Main Methods:
- Screening of Wisconsin dairy farm manure samples for E. coli O157:H7 and specific coliphages.
- Isolation and characterization of a specific coliphage (AR1) targeting E. coli O157:H7.
- Testing AR1 against a panel of enterobacteria to determine its specificity.
Main Results:
- No E. coli O157:H7 was detected in 21 manure samples.
- Nonspecific coliphages were found in 19 samples.
- A specific coliphage, AR1, was isolated, showing plaque formation on 14 E. coli O157:H7 strains but not on other E. coli.
- AR1 also plaqued on Shigella dysenteriae, suggesting a link to toxin production.
Conclusions:
- Coliphage AR1 demonstrates specificity for E. coli O157:H7.
- AR1's reactivity with S. dysenteriae suggests a potential marker for toxin-producing bacteria.
- AR1 may serve as a valuable tool for detecting E. coli O157:H7 and related pathogens in clinical, agricultural, and food samples.
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