Detection of verotoxin genes VT 1 and VT 2 in Escherichia coli O157:H7 in minced beef using immunocapture and real-time PCR.
Escherichia coli O157:H7 is a highly virulent pathogen that causes severe food poisoning in humans. Many outbreaks involving this pathogen have been linked to minced beef. A protocol is presented here to detect E. coli O157:H7 in minced beef. The method consists of an enrichment step in modified tryptone soya broth, followed by immunomagnetic separation and extraction of deoxyribonucleic acid. Real-time polymerase chain reaction, using hybridization probes, is used to detect the verotoxin genes 1 and 2 found in E. coli O157:H7. The assay has a detection limit of log10 3.5/mL E. coli O157:H7 cells in minced beef.
Fitzmaurice
Justine
J
Bacteriology, Investigation and Diagnostic Centre, Wallaceville, New Zealand.
D000818:Animals; D002417:Cattle; D004269:DNA, Bacterial / Q000032:analysis / Q000235:genetics / Q000302:isolation & purification; D019453:Escherichia coli O157 / Q000235:genetics / Q000302:isolation & purification*; D018189:Immunomagnetic Separation / Q000379:methods*; D008461:Meat Products / Q000382:microbiology*; D016133:Polymerase Chain Reaction / Q000379:methods*; D022622:Shiga Toxin 1 / Q000235:genetics*; D022641:Shiga Toxin 2 / Q000235:genetics*
D004269:DNA, Bacterial; D022622:Shiga Toxin 1; D022641:Shiga Toxin 2