IS1203v is an insertion sequence which has been found in inactivated Shiga toxin 2 genes of Escherichia coli O157:H7. We analyzed the transpositional mechanism of IS1203v in order to investigate whether the Shiga toxin 2 genes inactivated by IS1203v could revert to the wild type. When the transposase activity of IS1203v was enhanced by artificial frameshifting, IS1203v was obviously excised fro...

Addition of Shiga toxin 2 to human bone marrow or cord blood cell culture induced macrophage-granulocyte colonies. Although Shiga toxin 2 alone induced colonies mainly composed of macrophages, it induced colonies mainly consisting of granulocytes when combined with physiological doses of interleukin-1beta, granulocyte colony-stimulating factor, or stem cell factor with interleukin-3.

The production of Shiga toxin by a bacterial strain is necessary for induction of enteropathogenic haemolytic uraemic syndrome (HUS). Only strains that produce the toxin are associated with HUS. These include enterohaemorrhagic Escherichia coli, Shigella dysenteriae and rarely Citrobacter freundii [1, 2]. All strains associated with haemorrhagic colitis and HUS are Gram-negative, thus producing...

Infection of humans with Shiga toxin-producing Escherichia coli O157:H7 and Shigella dysenteriae 1 is strongly associated with vascular endothelial cell damage and the development of hemolytic-uremic syndrome. The cytotoxic effect of Shiga toxins on vascular endothelial cells in vitro is enhanced by prior exposure to bacterial lipopolysaccharide (LPS) or either of the host cytokines tumor necro...

Phages 933W, BAA2326, 434, and λ are evolutionarily-related temperate lambdoid phages that infect Escherichia coli. Although these are highly-similar phages, BAA2326 and 933W naturally encode Shiga toxin 2 (Stx⁺), but phage 434 and λ do not (Stx(-)). Previous reports suggest that the 933W Stx⁺ prophage forms less stable lysogens in E. coli than does the Stx(-) prophages λ, P22, and 434. The hig...

In this report, we present a PCR protocol for rapid identification of enterohemorrhagic Escherichia coli on a LightCycler instrument. In a multiplex assay, the genes encoding Shiga toxin 1 and Shiga toxin 2 are detected in a single reaction capillary. A complete analysis of up to 32 samples takes about 45 min.

The glycolipid-binding cytotoxin produced by Shigella dysenteriae 1, Shiga toxin, binds to MDCK cells (strain 1) only after treatment with short-chain fatty acids like butyric acid or with the tumor promoter 12-O-tetradecanoylphorbol 13-acetate. The induced binding sites were found to be functional with respect to endocytosis and translocation of toxin to the cytosol. Glycolipids that bind Shig...

Human intestinal cells lack globotriaosylceramide (Gb(3)), the receptor for Shiga toxin-1 (Stx1) and Shiga toxin-2 (Stx2). Therefore, the role of these toxins in mediating intestinal disease during infection with Shiga toxin-producing Escherichia coli is unclear. The aims of this study were to determine whether Stx1 and Stx2 induce apoptosis in epithelial cells expressing (HEp-2, Caco-2) or lac...

To estimate the prevalence of Shiga toxin producing Escherichia coli in Australia, bloody stool samples from two Australian locations were screened for the presence of Shiga toxin genes, stx1 and stx2. Four of 126 (3.2%) and 139 of 5,829 (2.4%) patients from the two locations had a positive polymerase chain reaction for Shiga toxin genes.