Detection of Escherichia coli by the nutrient agar plus 4-methylumbelliferyl beta-D-glucuronide (MUG) membrane filter method.
A two-step membrane filter procedure was evaluated to determine the ability to differentiate Escherichia coli from other coliform bacteria recovered from water. M-Endo LES agar incubated at 35 degrees C for 24 +/- 2 h was used as the initial isolation medium. Membranes containing coliform colonies were transferred to nutrient agar plus 4-methylumbelliferyl beta-D-glucuronide (MUG) and incubated for an additional 4 h at 35 degrees C. Escherichia coli colonies were distinguished by fluorescence when viewed under a long-wavelength ultraviolet light. A total of 119 MUG-positive colonies were isolated from 15 water sources, of which 115 (96.6%) were identified as E. coli. An examination of 182 pure culture environmental E. coli isolates revealed that 167 isolates (91.8%) exhibited fluorescence on the nutrient agar plus MUG medium. Survivors of E. coli cultures exposed to chlorination were also capable of producing a positive MUG reaction.
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Technical Support Division, United States Environmental Protection Agency, Cincinnati, Ohio 45268.
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Rice
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D015373:Bacterial Typing Techniques; D002713:Chlorine; D015169:Colony Count, Microbial; D003470:Culture Media; D004203:Disinfection; D004755:Enterobacteriaceae / Q000145:classification* / Q000254:growth & development; D004926:Escherichia coli / Q000145:classification* / Q000254:growth & development; D005453:Fluorescence; D005618:Fresh Water; D006923:Hymecromone / Q000031:analogs & derivatives / Q000378:metabolism; D008851:Micropore Filters; D014871:Water Microbiology
D003470:Culture Media; D006923:Hymecromone; D002713:Chlorine; C034888:4-methylumbelliferyl glucuronide