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Scalable Isolation and Purification of Extracellular Vesicles from Escherichia coli and Other Bacteria
Published on: October 13, 2021
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Glucuronidase-negative Escherichia coli in the ECOR Reference Collection
Rosalind A Lum1, George W Chang1
1Department of Nutritional Sciences, University of California, Berkeley, California 94720.
Journal of Food Protection
|April 27, 2019
Summary
Certain Escherichia coli strains lack beta-D-glucuronidase. Detection media like LT-MUGUR and Colilert are less effective for fecal E. coli than for urinary tract E. coli.
Area of Science:
- Microbiology
- Clinical Diagnostics
Background:
- Escherichia coli (E. coli) is a common bacterium.
- Some E. coli strains are beta-D-glucuronidase-negative.
- Accurate detection of E. coli is crucial for diagnosing infections.
Purpose of the Study:
- To evaluate the performance of two common E. coli detection media, LT-MUGUR and Autoanalysis-Colilert "MMO-MUG", in identifying beta-D-glucuronidase-negative strains.
- To compare the efficacy of these media for human fecal isolates versus urinary tract isolates.
Main Methods:
- Utilized the ECOR collection of E. coli isolates from diverse geographical origins.
- Tested human fecal and urinary tract isolates for beta-D-glucuronidase activity using LT-MUGUR and Autoanalysis-Colilert "MMO-MUG" media.
- Incubated cultures at 37°C for 24 hours.
Main Results:
- 34% of human fecal E. coli isolates were glucuronidase-negative in LT-MUGUR medium.
- 24% of human fecal E. coli isolates were glucuronidase-negative in Autoanalysis-Colilert "MMO-MUG" medium.
- None of the urinary tract E. coli isolates tested were glucuronidase-negative in either medium.
Conclusions:
- LT-MUGUR and Autoanalysis-Colilert "MMO-MUG" media show limitations in detecting all E. coli strains, particularly from human fecal samples.
- These diagnostic media appear more suitable for identifying E. coli from urinary tract infections compared to fecal samples.
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