Question:medium
All of the following have superantigen property EXCEPT:
All of the following have superantigen property EXCEPT:
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Think which of these toxins activates T-cells en masse versus one that just ADP-ribosylates a G protein in the gut.
Updated On: Jun 23, 2026
- Vibrio cholerae
- Streptococcal pyrogenic exotoxin
- Staphylococcal enterotoxins
- None of these
Show Solution
The Correct Option is A
Solution and Explanation
Mnemonic-led approach. Remember superantigens as the Staph and Strep toxins that whip up a cytokine storm by clamping MHC II to the T-cell receptor outside the peptide groove, switching on roughly 1 in 10 T-cells at once. The headline members are staphylococcal TSST-1, the staphylococcal enterotoxins, exfoliative toxin, and streptococcal pyrogenic exotoxins. Run option-elimination: option b (streptococcal pyrogenic exotoxin) and option c (staphylococcal enterotoxins) are both on that list, so both are true superantigens and cannot be the answer. Option a, Vibrio cholerae, makes cholera toxin, an enterotoxin that ADP-ribosylates the Gs protein, locks adenylate cyclase on, floods the enterocyte with cAMP and pours out watery stool. That is a classic enterotoxin mechanism with no T-cell cross-linking, so it is the odd one out. Answer: Vibrio cholerae.
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