Recent experiments using DNA transfection have shown that secretory proteins in AtT-20 cells are sorted into two biochemically distinct secretory pathways. These two pathways differ in the temporal regulation of exocytosis. Proteins secreted by the regulated pathway are stored in dense-core granules until release is stimulated by secretagogues. In contrast, proteins secreted by the constitutive...

The objective of this study was to determine feedlot- and pen-level fecal prevalence of seven enterohemorrhagic Escherichia coli (EHEC) belonging to serogroups (O26, O45, O103, O111, O121, O145, and O157, or EHEC-7) in feces of feedlot cattle in two feeding areas in the United States. Cattle pens from four commercial feedlots in each of the two major U.S. beef cattle areas were sampled. Up to 1...

A simultaneous direct detection of Shiga-toxin producing strains of E. coli (STEC; "Big Six" - O26, O45, O103, O111, O121, and O145) as well as O157 strains by optical biosensing with oligonucleotide-functionalized gold nanoparticles (AuNPs) was developed. Initially, conserved regions of stx genes were amplified by asymmetric polymerase chain reaction (asPCR). Pairs of single stranded thiol-mod...

Enteropathogenic Escherichia coli (EPEC) and enterohemorrhagic E. coli (EHEC) produce the characteristic "attaching and effacing" (A/E) lesion of the brush border. Intimin, an outer membrane protein encoded by eae, is responsible for the tight association of both pathogens with the host cell. Several eae have been cloned from different EPEC and EHEC strains isolated from humans and animals. The...

Shiga toxin-producing Escherichia coli (STEC) causes diarrhea and hemorrhagic colitis with life-threatening complications, such as hemolytic uremic syndrome. The aim of this study was to assess the molecular epidemiologic features of non-O157 STEC strains from different resources in China and illustrate the role of animal reservoirs or animal-derived foodstuffs in human STEC infections. A colle...

Recent data strongly suggest that the coatomer (COP) complex is involved in membrane transport between the ER and Golgi complex. This vesicular coat has been implicated in ER to Golgi, in intra Golgi as well as in Golgi to ER traffic. In this study we present a detailed immunocytochemical analysis of the distribution of β-COP in different tissue culture cells. Our results extend previous studie...

Strains of Shiga toxin-producing Escherichia coli (STEC) are a serious threat to the health, with approximately half of the STEC related food-borne illnesses attributable to contaminated beef. We developed an assay that was able to screen samples for several important STEC associated serogroups (O26, O45, O103, O104, O111, O121, O145, O157) and three major virulence factors (eae, stx 1 , stx 2)...

BACKGROUND Shiga toxin-producing Escherichia coli (STEC) O157:H7 is a well-recognized cause of bloody diarrhea and hemolytic-uremic syndrome (HUS). Non-O157 STEC contribute to this burden of illness but have been underrecognized as a result of diagnostic limitations and inadequate surveillance. METHODS Between 1983 and 2002, 43 state public health laboratories submitted 940 human non-O157 STE...