Detection of a heat-labile enterotoxin gene in enterotoxigenic Escherichia coli by densitometric evaluation using highly specific enzyme-linked oligonucleotide probes.
Two alkaline phosphatase-conjugated 24-mer oligonucleotide probes were developed to detect the heat-labile enterotoxin gene in enterotoxigenic Escherichia coli. Probes were antisense codon sequences, which are transcribed into mRNA, of the heat-labile enterotoxin gene of enterotoxigenic Escherichia coli of human origin. Using dot-blot hybridization, probes were tested with 100 clinical isolates and evaluated by a reflectance-type densitometer. Results agreed very well with those of an immunological test, the Biken test, and a 32P-labelled recombinant DNA probe. The oligonucleotide probes did not react with nucleic acids prepared from other diarrhoeagenic bacterial pathogens. Thus, the alkaline phosphatase-conjugated oligonucleotide probes seem to be highly sensitive and specific for detection of heat-labile enterotoxin-producing enterotoxigenic Escherichia coli. Moreover, the results indicate a potential usefulness for densitometric evaluation of DNA hybridization.
Tamatsukuri
S
S
Department of Bacteriology and Serology, Research Institute for Microbial Diseases, Osaka University, Japan.
Yamamoto
K
K
Shibata
S
S
Leaño
F
F
Honda
T
T
Miwatani
T
T
D000469:Alkaline Phosphatase / Q000378:metabolism; D001427:Bacterial Toxins / Q000235:genetics*; D001483:Base Sequence; D003720:Densitometry; D004768:Enterotoxins / Q000235:genetics*; D004926:Escherichia coli / Q000235:genetics*; D029968:Escherichia coli Proteins; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D009693:Nucleic Acid Hybridization; D015345:Oligonucleotide Probes / Q000235:genetics*; D012680:Sensitivity and Specificity; D014734:Vibrio cholerae / Q000235:genetics
D001427:Bacterial Toxins; D004768:Enterotoxins; D029968:Escherichia coli Proteins; D015345:Oligonucleotide Probes; C027538:heat-labile enterotoxin, E coli; D000469:Alkaline Phosphatase