Color enhanced transmission electron micrograph (TEM) of Clostridium botulinum. C. botulinum grows in badly preserved canned foods, notably meat and fish, and produces the potent exotoxin that causes botulism poisoning. The toxin affects the central nervous system of humans; in fatal cases death results from heart and lung failure due to malfunctions in the cardiac and respiratory centers of the brain. Magnifcation 10,000x at 10 cm.