Cholera Toxin B subunit (ctxB) Cholera is a protein complex secreted by the bacterium Vibrio cholerae. ctxB is responsible for the massive, watery diarrhea characteristic of cholera infection. The cholera toxin is an oligomeric complex made up of 6 protein subunits: a single copy of the A subunit and5 copies of the B subunit, denoted as AB5. Subunit B binds while subunit A activates the G protein which activates adenylate cyclase. The five B subunits form a five-membered ring. The A subunit has 2 important segments. The A1 portion of the chain (CTA1) is a globular enzyme payload that ADP-ribosylates G proteins, while the A2 chain (CTA2) forms an extended alpha helix which sits snugly in the central pore of the B subunit ring.
Cholera Toxin B subunit Recombinant produced in E.Coli is a single, non- glycosylated polypeptide chain containing 103 amino acids and having a molecular mass of 11.6kDa.ctxB is purified by proprietary chromatographic techniques.
