1893

Isolation of bacterial exotoxin from bacteria: Following botulism outbreak in Ellezelles, Belgium, microbiologist Emile Pierre-Marie van Emengem isolated the bacteria that caused it, Clostridium Botulinum. Emengem then separated the bacteria from the exotoxin, and tested the two separately in animal hosts. Whereas the bacteria were virtually harmless, the exotoxin alone caused the illness. “It was one of the earliest demonstrations in medical history of a bacterial exotoxin: a potent, secreted poison capable of producing disease in the absence of live bacteria.” At the Pasteur Institute around the same time, Emile Roux and Alexandre Yersin isolated the exotoxin responsible for diphtheria (Shahinpoor, loc 414-418).