Clostidium botulinum is a bacterium that produces the botulinum toxin. When loca
ID: 97649 • Letter: C
Question
Clostidium botulinum is a bacterium that produces the botulinum toxin. When locally applied, to parts of the face for example, neuromuscular transmission is blocked, and muscles that cause wrinkles cannot contract (no more wrinkles). How exactly does the toxin block nueromuscular transmissions? Botulinum toxin cleaves SNAP-25, blocking fusion of the vesicle Botuinum toxin cleaves the tethering proteins, inhibiting accumulation at the membrane Botulinum toxin cleaves the acetylcholine receptor Botulinum toxin stabilizes the link between synaptic vesicle and the axon terminal membraneExplanation / Answer
Botulinum toxin binds to the nerves which use the neurotransmitter acetylcholine. Once the toxin is bind to the receptor, it slowly gets taken up by the nerve cell. Inside the nerve cell, botulinum toxin cleaves SNAP25, a member of SNARE proteins preventing the release of neurotransmitter acetylcholine from the nerve endings. As acetylcholine is essential for neurotransmitter muscular transmission, botulinum toxin cause blockade of impulses. Therefore, the answer for this question is botulinum toxin cleaves SNAP25 blocking fusion of the vesicle (option 1).