Shigatoxin Activators

Shiga toxin, named after the Japanese microbiologist Kiyoshi Shiga, is a family of related toxins produced by certain strains of the bacteria Shigella dysenteriae and some serotypes of Escherichia coli (E. coli). These bacteria cause dysentery and gastroenteritis, respectively.Shiga toxin is a type of AB5 toxin, composed of one A subunit and a pentamer of five B subunits. The B subunits facilitate binding to a specific glycolipid on the surface of host cells, known as Gb3. The A subunit, once internalized, inhibits protein synthesis by cleaving a specific adenine residue from the 28S rRNA within the 60S ribosomal subunit. This action halts protein synthesis and leads to cell death.

The toxins are known for causing hemorrhagic colitis and hemolytic uremic syndrome (HUS), a serious condition characterized by hemolytic anemia, acute kidney failure, and low platelet count. HUS is a leading cause of acute kidney injury in children and can have severe long-term health implications.Shiga toxin's ability to cause such potent effects makes it a significant public health concern, especially in terms of foodborne illnesses. Outbreaks of Shiga toxin-producing E. coli (STEC) are often associated with contaminated food or water.