Evaluation of enzyme-labeled oligonucleotide probes to identify enterohaemorrhagic Escherichia coli.
Alkaline phosphatase-conjugated oligonucleotide probes were developed to detect the gene coding for Vero toxin 1 (VT1) and Vero toxin 2 (VT2). Using these probes, 3 hr was enough to detect VT genes when suspicious colonies of enterohaemorrhagic Escherichia coli (EHEC) were obtained on an agar plate. The results of a hybridization test with 144 isolates of EHEC O157 and one isolate of Shigella dysenteriae Type 1 agreed exactly with the immunological detection, reversed passive latex agglutination (RPLA) test, of VTs in their culture supernatants. The sensitivity levels of these probes for the detection of VT genes were 100%. The specificity of these probes were also tested with a total of 1,002 strains of Escherichia coli other than EHEC and 8 strains of Shigella sp. other than Shigella dysenteriae Type 1; the results showed 100% specificity.
Yoh
M
M
Research Center for Emerging Infectious Diseases, Osaka University, Japan. myon@bikin, osaka-u.ac.jp
Takagi
K
K
Eda
J
J
Ohtomo
M
M
Takarada
Y
Y
Shibata
S
S
Honda
T
T
D000469:Alkaline Phosphatase; D001427:Bacterial Toxins / Q000235:genetics* / Q000494:pharmacology; D004927:Escherichia coli Infections / Q000175:diagnosis / Q000382:microbiology*; D019453:Escherichia coli O157 / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity; D006471:Gastrointestinal Hemorrhage / Q000382:microbiology*; D007841:Latex Fixation Tests; D009693:Nucleic Acid Hybridization; D015345:Oligonucleotide Probes; D012680:Sensitivity and Specificity; D022622:Shiga Toxin 1; D022641:Shiga Toxin 2; D012760:Shigella / Q000235:genetics / Q000302:isolation & purification
D001427:Bacterial Toxins; D015345:Oligonucleotide Probes; D022622:Shiga Toxin 1; D022641:Shiga Toxin 2; D000469:Alkaline Phosphatase