Mechanism
The diphtheria toxin has the same mechanism of action as the enzyme NAD(+)—diphthamide ADP-ribosyltransferase (EC 2.4.2.36). It catalyzes the transfer of NAD+ to a diphthamide residue in eukaryotic elongation factor-2 (eEF2), inactivating this protein. It does so by ADP-ribosylating the unusual amino acid diphthamide. In this way, it acts as a RNA translational inhibitor. The catalysed reaction is as follows:
- NAD+ + peptide diphthamide nicotinamide + peptide N-(ADP-D-ribosyl)diphthamide
The cholera toxin and exotoxin A of Pseudomonas aeruginosa uses a similar mechanism of action.
Read more about this topic: Diphtheria Toxin
Famous quotes containing the word mechanism:
“Life is an offensive, directed against the repetitious mechanism of the Universe.”
—Alfred North Whitehead (1861–1947)
“The law isn’t justice. It’s a very imperfect mechanism. If you press exactly the right buttons and are also lucky, justice may show up in the answer. A mechanism is all the law was ever intended to be.”
—Raymond Chandler (1888–1959)
“I’ve never known a Philadelphian who wasn’t a downright “character;” possibly a defense mechanism resulting from the dullness of their native habitat.”
—Anita Loos (1888–1981)