An alkaline phosphatase-conjugated 27 - basc oligonucleotide probe was developed to detect the gene, bfPA, encoding the bundle-- forming pilus of enteropathogenic Escherichia coli (EPEC). The probe was proven to be hi...An alkaline phosphatase-conjugated 27 - basc oligonucleotide probe was developed to detect the gene, bfPA, encoding the bundle-- forming pilus of enteropathogenic Escherichia coli (EPEC). The probe was proven to be highly specific to EPEC, hybridizing only toEPEC strains, but not to Salmonella spp. Shigella spp., Vibrio spp., and other E. coli isolates. one hundred seventy eight E. colistrains belonging to traditional EPEC sergroups isolated from patients with diarrhoea were tested the probe, the prevalence rate of bfpAgene was 25. 28%. The frequency of the bfpA gene in relation to serogroups varied widely among EPEc The bfPA gene was morecommonly detected in strains of class l serogroups of EPEC(41.0% ) than in class I serogroups of EPEC(11.6% 6 % ). HEP- 2 cell adhesion assay and the fluorescent actin staining (FAS) test are 100% argreement, with all the localized adherence (LA) positive strainsproucing positive FAS activity. The results of bfpA probe hybridization were of 98.9% agreement with those obtained by using HEP- 2 cell adhesion assay and the FAS test. the sensitivity and specifity of the probe versus the FAS test and the HEP- 2 cell assay were95.7% and 100%, respectively. This probe was proven to be useful in identifying EPEC which carries the bfpA gene.展开更多
文摘An alkaline phosphatase-conjugated 27 - basc oligonucleotide probe was developed to detect the gene, bfPA, encoding the bundle-- forming pilus of enteropathogenic Escherichia coli (EPEC). The probe was proven to be highly specific to EPEC, hybridizing only toEPEC strains, but not to Salmonella spp. Shigella spp., Vibrio spp., and other E. coli isolates. one hundred seventy eight E. colistrains belonging to traditional EPEC sergroups isolated from patients with diarrhoea were tested the probe, the prevalence rate of bfpAgene was 25. 28%. The frequency of the bfpA gene in relation to serogroups varied widely among EPEc The bfPA gene was morecommonly detected in strains of class l serogroups of EPEC(41.0% ) than in class I serogroups of EPEC(11.6% 6 % ). HEP- 2 cell adhesion assay and the fluorescent actin staining (FAS) test are 100% argreement, with all the localized adherence (LA) positive strainsproucing positive FAS activity. The results of bfpA probe hybridization were of 98.9% agreement with those obtained by using HEP- 2 cell adhesion assay and the FAS test. the sensitivity and specifity of the probe versus the FAS test and the HEP- 2 cell assay were95.7% and 100%, respectively. This probe was proven to be useful in identifying EPEC which carries the bfpA gene.
