Expression of human alpha 1 interferon genes in vectors containing tandemly located promoters recognized by two different RNA polymerases (Escherichia coli and T7).

An expression vector containing two tandemly located promoters (T7 and P1) and two transcription terminators recognized by two different RNA polymerases (T7 RNA polymerase and Escherichia coli RNA polymerase) was constructed. Human alpha 1 interferon gene variants were cloned in this vector and their expression was studied in E. coli strains containing [E. coli BL2I (DE3)] or devoid (E. coli BL21) of the gene for the T7 RNA polymerase. We report that simultaneous activity of the two promoters reduces the level of gene expression when compared with the levels of expression corresponding to either P1 or T7 promoter alone.