Pseudogene IFN-alpha L: removal of the stop codon in the signal sequence permits expression of active human...

Biologically active interferon (10(6)-10(7) units/liter) was produced in Escherichia coli from modified human alpha interferon (IFN-alpha) pseudogene L. IFN-alpha pseudogene L has a stop codon in the signal peptide coding region. The region that contains the stop codon was replaced with the corresponding region of another human IFN-alpha gene, WA, that does not have a stop codon and was previously engineered for expression by fusion to the M13mp11 lac promoter. The interferon L fusion product was induced with IPTG after infecting E. coli JM103 with the M13 bacteriophage that contained the modified human IFN-alpha pseudogene L. Hence, the IFN-alpha L mature interferon coding sequence, which is not identical to any other alpha-interferon gene, has been conserved for active interferon coding information.