What are key characteristics of Clostridium botulinum?

• A. Anaerobic; Produces a heat labile neurotoxin; Toxins cause food poisoning; Spore forming
• B. Aerobic; Produces a heat-stable toxin; Toxins cause disease by colonization
• C. Facultative anaerobe; No toxin production; Non-spore-forming
• D. Aerobic; Non-toxin production; Spore-forming

Answer: (C)

Clostridium botulinum is an organism that thrives without oxygen, forms spores, and produces a toxin that is heat-labile. The disease it causes, botulism, comes from the toxin itself rather than the bacteria colonizing tissue, so it’s a toxin-mediated illness. The toxin interferes with the release of acetylcholine at neuromuscular junctions, leading to the characteristic flaccid paralysis. In foods, the danger lies in the toxin which can be destroyed by adequate heating, but the bacterial spores survive cooking and can germinate under anaerobic conditions to produce more toxin. So the best description is anaerobic; produces a heat-labile neurotoxin; toxins cause food poisoning; spore-forming. Descriptions that label it as aerobic or facultative, non-toxin-producing, or non-spore-forming don’t fit this organism.