Procholeragenoid: An Aggregated Intermediate in the Formation of Choleragenoid

Abstract

Abstract A high molecular weight polymer, designated “procholeragenoid,” is an intermediate in the heat-mediated conversion of the cholera exo-enterotoxin, choleragen, to the natural toxoid, choleragenoid. The demonstration of this polymer offers an explanation for the conversion of the toxin, ca. 90,000 m.w., to the antigenically identical toxoid, ca. 60,000 m.w., without apparent loss of a fragment. Isolated procholeragenoid has little residual toxicity and is immunogenic for mice.