Patent ID: 7052867

Claim:
An expression vector for the secretive production of human interferon alpha (hIFNα) comprising a polynucleotide encoding a modified thermostable enterotoxin II signal sequence and a polynucleotide encoding hIFNα ligated to the 3′-end thereof, wherein the modified thermostable enterotoxin II signal sequence is selected from the group consisting of: a polypeptide obtained by replacing the 4 th asparagine of the amino acid sequence of SEQ ID NO: 3 with threonine; a polypeptide obtained by replacing the 4 th asparagine and 22 nd tyrosine of the amino acid sequence of SEQ ID NO: 3 with threonine and glutamine, respectively; a polypeptide obtained by replacing the 4 th and 20 th asparagines of the amino acid sequence of SEQ ID NO: 3 with threonine and valine, respectively, and; a polypeptide obtained by replacing the 4 th asparagine, the 20 th asparagine and the 22 nd tyrosine of the amino acid sequence of SEQ ID NO: 3 with threonine, valine and glutamine, respectively.