Which bacterium causes botulism by producing botulinum neurotoxin?

Clostridium botulinum causes botulism by producing botulinum neurotoxin.

Clostridium botulinum is a group of anaerobic, spore-forming bacteria associated with soil, sediments, and improperly preserved foods. Under suitable conditions, some strains produce botulinum neurotoxin, which blocks the release of acetylcholine at neuromuscular junctions. The resulting illness causes weakness and characteristic descending flaccid paralysis.

Botulism can result from eating preformed toxin, from wound infection, or from intestinal colonization in infants. Food preservation is important because spores can survive ordinary cooking, while the toxin itself is heat-sensitive and can be destroyed by adequate heating. The name comes from the Latin botulus, meaning sausage, reflecting early links with sausage-associated outbreaks.

Clostridium tetani causes tetanus and produces a different neurotoxin that causes rigid muscle spasms. Clostridium perfringens is associated with gas gangrene and some food poisoning. Botulinum toxin also has carefully controlled medical and cosmetic uses, but its therapeutic use does not change the organism responsible for botulism.