What kinds of toxins are produced by Shigella?

Shiga toxins (Stx) are cytotoxins involved in severe human intestinal disease. These toxins are commonly found in Shigella dysenteriae serotype 1 and Shiga-toxin–producing Escherichia coli; however, the toxin genes have been found in other Shigella species.

Does Shigella produce toxin?

Shigella dysenteriae is more common in developing countries and is the only type of Shigella that is usually known to produce Shiga toxin.

What is the mechanism of action of Shiga toxin?

Mechanism. The B subunits of the toxin bind to a component of the cell membrane known as glycolipid globotriaosylceramide (Gb3). Binding of the subunit B to Gb3 causes induction of narrow tubular membrane invaginations, which drives formation of inward membrane tubules for the bacterial uptake into the cell.

What does Shiga toxin cause?

Shiga toxin-producing Escherichia coli (STEC) are bacteria that can cause bloody diarrhea in infected people. In rare cases, the same bacterium can also cause a kidney disease known as Hemolytic Uremic Syndrome. The most well known member of this group of bacteria is E. coli O157:H7.

Is the Shiga toxin the same as verotoxin?

The purified toxin was later shown to be equivalent to Shiga toxin from Shigella dysenteriae ( O’Brien et al., 1982) and has therefore been termed Shiga-like toxin or Shiga toxin (Stx) also. There is a single amino acid difference between Stx1 and VT1 ( Strockbine et al., 1988 ).

Is the Shiga toxin found in Escherichia coli?

Stx is found in Shigella dysenteriae 1 and in some serogroups of Escherichia coli (called Stx1 in E. coli). In addition to or instead of Stx1, some E. coli strains produce a second type of Stx, Stx2, that has the same mode of action as Stx/Stx1 but that is antigenically distinct.

Where did the discovery of verotoxin come from?

Verotoxin was discovered in Canada in 1976 as an additional cytopathic effect on vero cells exhibited by extracts of certain E. coli strains (Konowalchuk et al., 1977).

How is Shiga toxin related to uremic syndrome?

[Katherine Lamba] The treatment may depend on which type of bacteria is producing the Shiga toxin. In the United States, Shiga toxins are still most commonly associated with infections due to Shiga toxin-producing E. coli. Shigella sonnei and Shiga toxin Page 3 of 3 April 2016 uremic syndrome.