Patent ID: 7556817

Claim:
A recombinantly modified Clostridial toxin comprising an enzymatic domain having a zinc-dependent endopeptidase activity which targets a soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) protein, a translocation domain, a binding domain and a modified di-chain loop region, the modified di-chain loop region intervening between the enzymatic domain and the translocation domain; wherein the di-chain loop region modification comprises a Clostridial toxin substrate cleavage site from a SNARE protein of at most 40 amino acids in length located within the di-chain loop region that can be proteolytically cleaved by the enzymatic domain of the recombinantly modified Clostridial toxin; and wherein expression of the recombinantly modified Clostridial toxin within a cell results in single chain to di-chain conversion of the recombinantly modified Clostridial toxin due to proteolytic cleavage of the Clostridial toxin substrate cleavage site.