E. COLI EXPRESSION PLASMID WITH LAC PROMOTOR REPRESSOR GENE

摘要

A novel Escherichia coli plasmid is described. The plasmid has, between the Shine-Dalgarno sequence and the translation start codon, a base sequence different from the corresponding, originally occurring region in the beta -galactosidase operon and contains, upstream therefrom, the region of a hybrid promoter between the Escherichia coli trp promoter and the lac promoter and, at an entirely independent site, a lac promoter repressor gene. Employing an Escherichia coli transformant carrying the plasmid, a useful polypeptide such ash-IFN- gamma can be produced in high yield.