Microbiology · Gram-Positive Bacteria (Staphylococcus, Streptococcus, Clostridium, Diphtheria)

An infant develops constipation, weak cry, and generalized hypotonia after consuming honey. Botulism is suspected. The botulinum toxin causes flaccid paralysis by preventing the release of acetylcholine at the neuromuscular junction. Which specific SNARE protein is cleaved by botulinum toxin type B?

  • A SNAP-25
  • B Syntaxin
  • C Synaptobrevin
  • D Synaptotagmin
Correct answer: C. Synaptobrevin

Explanation

Botulinum toxin type B cleaves synaptobrevin, a vesicle-associated membrane protein. Botulinum toxin types A and E cleave SNAP-25. Botulinum toxin type C1 cleaves syntaxin. Synaptotagmin is a calcium sensor and not a target of botulinum toxin. Synaptobrevin cleavage prevents vesicle fusion.

Reference: Ananthanarayan and Panicker's Textbook of Microbiology, 11th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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