Cholera Toxin B Subunit

Cholera toxin (also known as choleragen and sometimes abbreviated to CTX, Ctx or CT) is protein complex secreted by the bacterium Vibrio cholerae. CTX is responsible for the massive, watery diarrhea characteristic of cholera infection. The cholera toxin is an oligomeric complex made up of six protein subunits: a single copy of the A subunit (part A, enzymatic), and five copies of the B subunit (part B, receptor binding), denoted as AB5. Subunit B binds while subunit A activates the G protein which activates adenylate cyclase.

Cholera Toxin B Subunit

The B subunit pentameric ring directs the A subunit to its target by binding to the GM1 gangliosides present on the surface of the intestinal epithelial cells. It can bind five GM1 gangliosides. It has no toxic activity by itself.

Killing of cells of other organism Source: TIGR
Pathogenesis Source: TIGR
Positive regulation of tyrosine phosphorylation of STAT protein Source: CACAO
Protein ADP-ribosylation Source: TIGR

Secreted; Host cell membrane