Microbiology The mechanism of action of the exotoxin produced by Corynebacterium diphtheriae can be characterized by which of the following? A Acting as a superantigen that binds to MHC class II protein and the T-cell receptor B Blocking the release of acetylcholine causing anticholinergic symptoms C Blocking the release of glycine D Inhibits protein synthesis EF-2 adenosine diphosphate (ADP) ribosylation. 💡 Explanation The mechanism of action of the exotoxin produced by Corynebacterium diphtheriae can be characterized by which of the following? ✓ Correct Answer: D. Inhibits protein synthesis EF-2 adenosine diphosphate (ADP) ribosylation.