Vaccines targeting enterohaemorrhagic Escherichia coli (EHEC) O157:H7 shedding in cattle are only partially protective. The correlates of protection of these vaccines are unknown, but it is probable that they reduce bacterial adherence at the mucosal surface via the induction of blocking antibodies. Recent studies have indicated a role for cellular immunity in cattle during colonisation, provid...

The locus of enterocyte effacement (LEE) is a chromosomal pathogenicity island that encodes the proteins involved in the formation of the attaching and effacing lesions by enterohemorrhagic Escherichia coli (EHEC) and enteropathogenic E. coli (EPEC). The LEE comprises 41 open reading frames organized in five major operons, LEE1, LEE2, LEE3, tir (LEE5), and LEE4, which encode a type III secretio...

Escherichia coli O103, harbored in the hindgut and shed in the feces of cattle, can be enterohemorrhagic (EHEC), enteropathogenic (EPEC), or putative non-pathotype. The genetic diversity particularly that of virulence gene profiles within O103 serogroup is likely to be broad, considering the wide range in severity of illness. However, virulence descriptions of the E. coli O103 strains isolated ...

A multiplex real-time PCR (R-PCR) assay was designed and evaluated on the ABI 7700 sequence detection system (TaqMan) to detect enterohemorrhagic Escherichia coli (EHEC) O157:H7 in pure cultures, feces, and tissues. Three sets of primers and fluorogenic probes were used for amplification and real-time detection of a 106-bp region of the eae gene encoding EHEC O157:H7-specific intimin, and 150-b...

Citrobacter rodentium is a classically noninvasive pathogen of mice that is similar to enteropathogenic Escherichia coli (EPEC) in man. Following oral infection of young mice, the organism colonizes the distal colon, and within 1 week the colonic mucosa doubles in thickness and there is massive epithelial cell hyperplasia. Since T-cell responses in mouse models of inflammatory bowel disease (IB...

Enterohemorrhagic Escherichia coli O157:H7 translocates 2 effectors to trigger localized actin assembly in mammalian cells, resulting in filamentous actin "pedestals." One effector, the translocated intimin receptor (Tir), is localized in the plasma membrane and clustered upon binding the bacterial outer membrane protein intimin. The second, the proline-rich effector EspF(U) (aka TccP) activate...

Saccharomyces boulardii has received increasing attention as a probiotic effective in the prevention and treatment of infectious and inflammatory bowel diseases. The aim of this study was to examine the ameliorating effects of S. boulardii on Citrobacter rodentium colitis in vivo and identify potential mechanisms of action. C57BL/6 mice received 2.5 x 10(8) C. rodentium by gavage on day 0, foll...

We investigated the genetic relationships of 54 Escherichia coli O103 strains from humans, animals, and meat by molecular typing of housekeeping and virulence genes and by pulsed-field gel electrophoresis (PFGE). Multilocus sequence typing (MLST) of seven housekeeping genes revealed seven profiles, I through VII. MLST profiles I plus III cover 45 Shiga toxin-producing E. coli (STEC) O103:H2 str...

The current study was designed to determine the prevalence of antimicrobial resistance and virulence genes in Escherichia coli isolated from canine diarrheal cases. Fecal samples were collected 77 dogs with clinical diarrhea 10 non-diarrheic dogs. Breed, age sex, manifestations recorded. Samples plated on MacConkey EMB agars, followed by standard isolation procedures identification E. coli. An ...