Recombinant DNA and expression vector for the repressible and inducible expression of foreign genes

摘要

The recombinant DNA according to the present invention contains a regulator region which is different from the pfl gene; a promoter region upstream from the gene which contains a -35/-10 promoter sequence; a regulator region upstream from the promoter region which contains a sequence (I) 5'-GAGATATGATCTATATCAATTTC-3' or a 23 base pair sequence which is at least 80% identical to positions 6-10 and 15-19 of said sequence (I) but not having C at position 8 and/or G at position 17. An expression vector according to the present invention contains a recombinant DNA according to the present invention ligated into a suitable vector molecule and methods are also described for expression the DNA.