What is the mechanism of action of Shiga toxin?

What is the mechanism of action of Shiga toxin?

The Shiga toxin (a non-pore forming toxin) is transferred to the cytosol via Golgi network and endoplasmic reticulum (ER). From the Golgi toxin is trafficked to the ER. Shiga toxins act to inhibit protein synthesis within target cells by a mechanism similar to that of the infamous plant toxin ricin.

How do Shiga toxins inhibit protein synthesis?

The Stxs (also known as Vero toxins, and previously as Shiga-like toxins) are a group of bacterial AB5 protein toxins of about 70 kDa that inhibit protein synthesis in sensitive eukaryotic cells. Protein synthesis is blocked by the Stxs through the removal of an adenine residue from the 28S rRNA of the 60S ribosome.

Which type of toxin is Shiga toxin?

Shiga toxins (Stxs) expressed by STEC are highly cytotoxic class II ribosome-inactivating proteins and primary virulence factors responsible for major clinical signs of Stx-mediated pathogenesis, including bloody diarrhea, hemolytic uremic syndrome (HUS), and neurological complications.

What does Shiga toxin do to cells?

The Shiga toxins reach the Gb3-expressing intestinal endothelial cells, causing cell damage and cell death. Damage to the intestinal endothelium causes mucosal and submucosal edema, hemorrhage, and bloody diarrhea. The onset of HC with these symptoms can be a sign for the development of HUS after a few days.

How is Shiga toxin transmitted?

Some strains however, such as Shiga toxin-producing E. coli (STEC), can cause severe foodborne disease. It is transmitted to humans primarily through consumption of contaminated foods, such as raw or undercooked ground meat products, raw milk, and contaminated raw vegetables and sprouts.

How does Shiga toxin cause diarrhea?

They are some of the most common strains to cause severe food-related illness in people. It’s different from other E. coli because it makes a potent toxin called shiga toxin. This toxin damages the lining of the intestinal wall, causing bloody diarrhea.

How does Shiga toxin cause bloody diarrhea?

Is Shiga toxin endotoxin or exotoxin?

protein exotoxin
Shiga toxin (Stx) is a protein exotoxin expressed by the Gram-negative bacteria Shigella dysenteriae serotype 1.

What is Shiga toxin genes PCR?

PCR detection of stx, the gene encoding Shiga toxin, directly from fecal specimens is a sensitive and specific technique, providing same-day results. PCR assay identifies non-O157:H7 Shiga toxin-producing bacteria, extending the utility beyond strains identifiable on SMAC agar.

How serious is Shiga toxin?

If Shiga toxin gets into the bloodstream it can cause kidney failure. “This is especially common in children; about 15% of kids with Shiga toxin-producing E. coli infections get kidney disease, and some can suffer long term kidney damage,” says UConn Health immunologist Sivapriya Vanaja.

How does a child get Shiga toxin?

Infected food handlers can contaminate food if they do not wash their hands properly after going to the bathroom and handle food that other people eat. The bacteria can also be spread in settings such as child care centers, where hands contaminated while changing diapers can spread the disease.

What is the PDB number for Shiga toxins?

From PDB: 1R4Q ​. Shiga toxins are a family of related toxins with two major groups, Stx1 and Stx2, expressed by genes considered to be part of the genome of lambdoid prophages. The toxins are named after Kiyoshi Shiga, who first described the bacterial origin of dysentery caused by Shigella dysenteriae.

Is there a Shiga toxin in Escherichia coli?

Shiga toxin not detected by immunoassay, suggesting that a Shiga toxin–producing Escherichia coli, such as E. coli O157, is not present Genes for Shiga toxin 1, Shiga toxin 2, or both were detected by polymerase chain reaction, indicating the likely presence of a Shiga toxin–producing Escherichia coli such as O157:H7

What is Shiga toxin type 1 and Type 2?

Shiga toxin type 1 and type 2 (Stx-1 and 2) are the Shiga toxins produced by some E. coli strains.

What is the PMID for Shiga toxin 2 (Shiga toxin 2)?

PMID 18754742. ^ Tironi-Farinati C, Loidl CF, Boccoli J, Parma Y, Fernandez-Miyakawa ME, Goldstein J (May 2010). “Intracerebroventricular Shiga toxin 2 increases the expression of its receptor globotriaosylceramide and causes dendritic abnormalities”.