MOLECULAR SIZE OF CLOSTRIDIUM BOTULINUM TYPE E TOXIN IN ^|^ldquo;IZUSHI^|^rdquo;

Abstract

Botulogenic "izusht" was prepared from flounders inoculated with spores of Clostridium botulinum type E by the method commonly practiced In the locaTareas. To determine the molecular size and the properties of the toxin In "izushl," the exudate of the "Izushi" and the extract of the fish were subjected to gel filtration on Sephadex G-100 and ultracentrlfugal separation in sucrose density gradient. Most of the toxin in "izushi" was proved to be in the form of precursor and to possess a large molecular size with a sedimentation constant (s20.w) of about 11.5. The tryptic activation of the precursor In the "izushi" caused no appreciable reduction in the molecular size.