The stx genes of many Shiga toxin-encoding Escherichia coli (STEC) strains are encoded by prophages of the lambda bacteriophage family. In the genome of the Stx1-encoding phage H-19B, the stx(1)AB genes are found approximately 1 kb downstream of the late phage promoter, p(R)', but are known to be regulated by the associated iron-regulated promoter, p(Stx1). Growth of H-19B lysogens in low iron ...

We describe here the isolation and identification of a Shiga toxin 1 (Stx1)-producing Enterobacter cloacae strain, M12X01451, from a human clinical specimen. The bacterial isolate was identified as E. cloacae using a polyphasic approach that included phenotypic, genetic, and proteomic analyses. The M12X01451 stx1 was sequenced, and the holotoxin was found to share only 87% amino acid sequence i...

The discovery that bovine peripheral lymphocytes are sensitive to Stx1 identified a possible mechanism for the persistence of infections with Shiga toxin (Stx)-producing Escherichia coli (STEC) in the bovine reservoir host. If intraepithelial lymphocytes (IEL) are also sensitive to Stx1, the idea that Stx1 affects inflammation in the bovine intestine is highly attractive. To prove this hypothes...

Bovine colonic crypt cells express CD77 molecules that potentially act as receptors for Shiga toxins (Stx). The implication of this finding for the intestinal colonization of cattle by human pathogenic Stx-producing Escherichia coli (STEC) remains undefined. We used flow cytometric and real-time PCR analyses of primary cultures of colonic crypt cells to evaluate cell viability, CD77 expression,...

Shiga toxin-producing Escherichia coli (STEC) is an important food-borne pathogen that causes hemolytic-uremic syndrome. Following ingestion, STEC cells colonize the intestine and produce Shiga toxins (Stx), which appear to translocate across the intestinal epithelium and subsequently reach sensitive endothelial cell beds. STEC cells produce one or both of two major toxins, Stx1 and Stx2. Stx2-...

BACKGROUND Shiga toxin-producing E. coli (STEC) are a group of common and potentially deadly intestinal pathogens expressing Shiga toxin (Stx) as a primary virulence factor. Of the two types of Stx, Stx2 is responsible for more severe symptoms during infection, while Stx1 is almost identical to the Shiga toxin from Shigella dysenteriae, a ubiquitous pathogen in developing countries. Although an...

All over the world, Escherichia coli (STEC), which produces Shiga toxin, is recognized as an important zoonotic pathogen. Ruminants, particularly cattle, are their main reservoirs, but role of small ruminants in epidemiology human infections has not been extensively evaluated many countries. In this study, it was aimed to determine toxin subtypes Stx1, Stx2, eae and ehxa genes producing isolate...

Shiga toxins (Stx) are primarily associated with Shiga toxin-producing Escherichia coli and Shigella dysenteriae serotype 1. Stx production by other shigellae is uncommon, but in 2014, Stx1-producing S. sonnei infections were detected in California. Surveillance was enhanced to test S. sonnei isolates for the presence and expression of stx genes, perform DNA subtyping, describe clinical and epi...

Shiga toxin-producing Escherichia coli (STEC) is widespread in the cattle population, but the clinical significance of Shiga toxins (Stx's) for the bovine species remains obscure. Since Stx's exert immunomodulating effects in other species, we examined the effect of purified Stx1 on a bovine B lymphoma cell line (BL-3) and peripheral blood mononuclear cells (PBMC) isolated from adult bovine blo...

Thrombocytopenia caused by platelet consumption in thrombi is a major manifestation of hemolytic uremic syndrome (HUS) associated with Shiga toxin (Stx) producing Escherichia coli. Platelets have glycosphingolipid receptors capable of binding Stx, but a direct interaction between the toxin and platelets, leading to platelet activation, has not been reported. In this study, it is shown that Stx1...