Http://www.biochemj.org | Equinatoxin II (Eqt-II) is a member of the actinoporins, a uniquefamily of cytotoxins comprising 20 kDa pore-forming proteinsisolated from sea anemones. Actinoporins bind preferentially tolipid membranes containing sphingomyelin, and create cationselectivepores by oligo...
Evaluación de técnicas moleculares e inmunoenzimáticas para la detección de E coli enterohemorrágico en brotes de toxi-infecciones alimentarias/ Evaluation of molecular and immunoenzymatic assays for detecting Enterohemorrhagic E coli in food borne outbreaks
Resumen en inglés Background: Enterohemorrhagic Escherichia coli (EHEC), is an emergent pathogen that causes sporadic infections and outbreaks of gastroenteritis associated with consumption of contaminated food products. Because detection of EHEC in diarrhea patients is not routinely performed, infection is most probably underestimated. Aim: To compare three techniques to detect EHEC: Colony hybridization with DNA probes, polymerase chain reaction (PCR) for the detection of stx1 and stx2 g (mas) enes and immunoenzymatic detection by ELISA (Premier EHEC) of Stx1 and Stx2 toxins. Material and methods: Four outbreaks of food-borne gastroenteritis were studied including 16 patients and 78 strains of E coli. Twenty one (26,9%) strains, hybridized with the stx1 probe, 1 (1,3%) hybridized only with the stx2 probe and 36 (46,1%) with both probes. PCR amplification for cytotoxin genes was observed in 6 strains (7,7%) from the second outbreak studied. The immunoenzimatic assay detected the cytotoxins in 18 (23,0%), of the 78 studied strains. Agreement between probes and ELISA was 44,8%, between PCR and probes 34,7% and 82,4% between ELISA and PCR. Conclusions: These results indicate a variable yield among different EHEC detection techniques. Considering PCR as the gold standard, ELISA technique showed a better sensitivity and specificity than probes (Rev Méd Chile 2002; 130: 603-9)