We report here the use of immunomagnetic (IM) electrochemiluminescence (ECL) for quantitative detection of Esherichia coli O157:H7 in water samples following enrichment in minimal lactose broth (MLB). IM beads prepared in-house with four commercial anti-O157 monoclonal antibodies were compared for efficiency of cell capture. IM-ECL responses for E. coli O157:H7 (strain SEA13B88) were similar fo...

We have isolated one sorbitol-nonfermenting (SNF) Escherichia coli O157:H7 isolate and five sorbitol-fermenting (SF) E. coli O157:H(-) isolates that do not contain Shiga toxin (Stx) genes (stx). Isolates originated from patients with diarrhea (n = 4) and hemolytic-uremic syndrome (HUS) (n = 2). All isolates harbored a chromosomal eae gene encoding gamma-intimin as well as the plasmid genes E-hl...

escheric hia coli o157:h7 lives in the intestines of healthy cattle, and can contaminate meat during slaughtering pr actices . detection of the low infectious dosage of bacterium requires a sensitive method. we developed polymerase chain reaction (pcr) assays to detect the gene stx2 irrespective of the bacterial serotype. in this study, the detection limit of the pcr protocol in detecting stx2 ...

W e have read with interest the Letter to the Editor by Ahmed and Abouzeed reporting on the important issue of enterohemorrhagic Escherichia coli O157 (EHEC O157) in dairy cattle in Libya (1). Based on two cited references, the authors state that: ‘‘Surveys of diarrheal stools from children in African nations, including Libya, have detected EHEC O157 in 8 15% of the samples’’. One of the cited ...

Modified tryptic soy broth, lauryl sulfate tryptose broth, modified EC broth, sorbitol MacConkey agar and Fluorocult E. coli O157 agar were tested for the recovery of 3 strains of Escherichia coli O157:H7 against E. coli type 1 and Citrobacter freundii as common competitive microflora of raw meat products. Two-stepped trials showed that modified EC broth and lauryl sulfate tryptose broth were s...

The duration of shedding of Escherichia coli O157 isolates by hay-fed and grain-fed steers experimentally inoculated with E. coli O157:H7 was compared, as well as the acid resistance of the bacteria. The hay-fed animals shed E. coli O157 longer than the grain-fed animals, and irrespective of diet, these bacteria were equally acid resistant. Feeding cattle hay may increase human infections with ...

AIMS Survival of Escherichia coli O157:H7 and nonpathogenic E. coli on spinach leaves and in organic soil while growing spinach in a growth chamber was investigated. METHODS AND RESULTS Spinach plants were maintained in the growth chamber at 20 degrees C (14 h) and 18 degrees C (10 h) settings at 60% relative humidity. Five separate inocula, each containing one strain of E. coli O157:H7 and o...

background: enterohemorrhagic escherichia coli (ehec) o157:h7 is an infectious zoonotic pathogen causing human infections. these infections, in some cases, can lead to hemolytic uremic syndrome and its life-threatening complications and even death worldwide. the first intimate bacterial adhesion, intimin (i), with its own receptor translocated intimin receptor (tir) and e. coli secreted protein...

Twelve ruminally cannulated cattle, adapted to forage or grain diet with or without monensin, were used to investigate the effects of diet and monensin on concentration and duration of ruminal persistence and fecal shedding of E. coli O157:H7. Cattle were ruminally inoculated with a strain of E. coli O157:H7 (10(10) CFU/animal) made resistant to nalidixic acid (Nal(r)). Ruminal and fecal sample...

A novel, fast and sensitive determination strategy for E. coli O157:H7 has been developed by combination of ligandmagnetic nanoparticles (LMNPs) enrichment with a fluorescent silica nanoparticles (FSiNPs) based two-color flow cytometry assay (LMNPs@FSiNPs-FCM). E. coli O157:H7 was first captured and enriched through the lectin concanavalin A (Con A) favored strong adhesion of E. coli O157:H7 to...