In recent studies, strains of non-dysenteriae 1 Shigella (NDS) expressing Shiga toxin have been reported. In this study, we report a novel stx1a-converting bacteriophage of Shigella sonnei associated with travel to Mexico. Phylogenetic comparison between this and other stx-converting phages suggests that toxigenic NDS strains have arisen through separate horizontal transfer events from toxigeni...

Issues of water quality are a global problem with potentially devastating results in communities if microbial levels are not monitored and controlled effectively.This is especially true with the potential threat of bioterrorist contamination of water supplies.This study presents a method for quantifying microbial water pathogens by 5' nuclease real-time polymerase chain reaction analysis, thus ...

Shiga-toxigenic Escherichia coli strains belonging to serotype O157 are important human pathogens, but the genetic basis of expression of the O157 antigen and the role played by the lipopolysaccharide O side chain in the adherence of this organism to epithelial cells are not understood. We performed TnphoA mutagenesis on E. coli O157:H7 strain 86-24 to identify a mutant (strain F12) deficient i...

Diarrhea is an important hygienic problem in under development countries. Among pathogenic agents Escherichia coli is the most etiologic agent of diarrhea in children below five years old. Some E. coli strains produce cytotoxins that have cytopathic effect on vero cell and identified as verotoxin. This study performs for resolve frequency of Vero Toxigenic Escherichia coli...

Cytolethal distending toxins (CDT) are potent cytotoxins of several Gram-negative pathogenic bacteria, including Escherichia coli, in which five types (CDT-I to CDT-V) have been identified so far. CDT-V is frequently associated with Shiga-toxigenic E. coli (STEC), enterohemorrhagic E. coli (EHEC) O157 strains, and strains not fitting any established pathotypes. In this study, we were the first ...

Shiga-toxigenic Escherichia coli (STEC) are causative agents of bloody diarrhoea, haemorrhagic colitis (HC) and haemolytic uraemic syndrome (HUS). Humans acquire infections primarily through contaminated beef. In India, STEC has not been implicated as a major cause of diarrhoea. The study was carried out to know the prevalence of shiga toxin (ST) producing Escherichia coli (STEC) and virulence ...

In this study, 200 Escherichia coli isolates from 22 rainwater tank samples in Southeast Queensland, Australia, were tested for the presence of 20 virulence genes (VGs) associated with intestinal and extraintestinal pathotypes. In addition, E. coli isolates were also classified into phylogenetic groups based on the detection of the chuA, yjaA, and TSPE4.C2 genes. Of the 22 rainwater tanks, 8 (3...

Despite these advances, there is still a group of infants with AGE who despite conventional treatment and exclusion of all carbohydrates from the diet INTRODUCTION In recent years there have been a number of advances facilitating our understanding of the pathogenesis of acute gastroenteritis (AGE) in infancy and childhood. The discovery by Bishop et al. (1973) of the aetiological significance o...

OBJECTIVE To investigate whether the HlyA-induced vacuolating effect is produced by V. cholerae O1 ElTor strains isolated from different geographic origins, including Mexico. MATERIAL AND METHODS Supernatant-induced haemolysis, vacuolating activity and cytotoxicity in Vero cells were recorded. PCR, RFLP analysis and molecular cloning were performed. RESULTS All ElTor strains analyzed induce...