Structure of alpha-bungarotoxin (blue) in complex with the alpha-9 nAChR subunit (orange), showing interactions with loops I and II.<unk> -neurotoxins antagonistically bind irreversibly to nAChRs of skeletal muscles, thereby blocking the action of ACh at the postsynaptic membrane, inhibiting ion flow and leading to paralysis. nAChRs contain two binding sites for snake venom neurotoxins. The observation that a single molecule of the toxin suffices to inhibit channel opening is in agreement with experimental data on the amount of toxin per receptor. Some computational studies of the mechanism of inhibition using normal mode dynamics suggest that a twist-like motion caused by ACh binding may be responsible for pore opening, and that this motion is inhibited by toxin binding.
Α-Bungarotoxin
Β-Bungarotoxin
Alpha-neurotoxin
Kurtoxin
Dinotoxin
Kaliotoxin
Neurotoxin
Psalmotoxin