Microbiological process.

摘要

A toxoid comprising an inactive form of a toxin or toxic component of a toxin, which inactivate form is substantially homologous with said toxin or toxic component, is produced by expression of a modified gene and is substantially non-toxic while being, alone or in combination with one or more non-toxic components, capable of stimulating the production of antibodies against the said toxin or toxic component is described. The toxoid may be used in vaccine preparations. A toxoid has been developed which is of use in the treatment of pig scours. A method of producing the toxoid is described using recombinant DNA technology.