A child has a gray pseudomembrane over the tonsils and a bull neck. Which toxin action causes the disease?
Answer and explanation
Correct answer: B. ADP-ribosylation of elongation factor 2
- Step 1: The pseudomembrane and bull neck suggest Corynebacterium diphtheriae. Step 2. Its toxin inactivates elongation factor 2 and stops protein synthesis. Answer: ADP-ribosylation of elongation factor 2. Why not the others: adenylate cyclase activation is cholera, SNARE cleavage is clostridial and superantigens are toxic shock syndrome.
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