Detection of Escherichia coli O157:H7 in heifers' faecal samples using an automated immunoconcentration system
| Autor: | S. Ray-Gueniot, V. Atrache, C. Mazuy, C. Vernozy-Rozand, A. Meyrand, C. Bavai, M.P. Montet, P. Feng, L. Villard |
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| Rok vydání: | 2000 |
| Předmět: |
food.ingredient
Bacterial Toxins Sorbitol-MacConkey agar Cattle Diseases Virulence Biology Escherichia coli O157 medicine.disease_cause Polymerase Chain Reaction Shiga Toxin 2 Applied Microbiology and Biotechnology Enrichment culture Microbiology Feces chemistry.chemical_compound fluids and secretions food medicine Animals Sorbitol Agar Adhesins Bacterial Escherichia coli Alleles Escherichia coli Infections Glucuronidase Immunomagnetic Separation Escherichia coli Proteins biology.organism_classification Enterobacteriaceae Culture Media Animals Newborn chemistry Immunologic Techniques Cattle biological phenomena cell phenomena and immunity Carrier Proteins Cefixime Bacterial Outer Membrane Proteins Plasmids medicine.drug |
| Zdroj: | Letters in Applied Microbiology. 30:217-222 |
| ISSN: | 0266-8254 |
| Popis: | Pre-treatment of a 5-h enrichment culture with an automated immunoconcentration (ICE) system greatly improved the isolation of Escherichia coli O157:H7 from spiked heifer faecal samples. Enrichment samples plated directly onto sorbitol MacConkey agar (SMAC) and SMAC agar supplemented with cefixime and potassium tellurite (CT-SMAC) showed recovery rates of 8% and 56%, respectively. However, after ICE treatment, E. coli O157:H7 was recovered from 92% of the samples on SMAC and 100% on CT-SMAC. Immunoconcentration analysis of heifers' faecal samples collected from a slaughter-house in France, during March to June 1998, showed that 1% (three of 300) was positive for E. coli O157:H7. Phenotypic and genotypic analysis showed that all three isolates carried both the O157 and H7 antigens, did not ferment sorbitol or had beta-glucuronidase activity and carried trait virulence factors for E. coli O157:H7 (uidA allele, eaeA and pO157 plasmid). However, only one strain was toxigenic and this strain produced a single toxin, namely verotoxin 2. |
| Databáze: | OpenAIRE |
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