| abstract |
There are disclosed E. Coli expression plasmid vectors useful for expressing foreign genes. The vectors contain (a) a fragment of the plasmid pBR322 containing the origin of replication, (b) a DNA fragment containing the coding sequence of the temperature-sensitive repressor CI857S7 from bacteriophage lambda, (c) the strong leftward promoter, P L , from bacteriophage lambda, and (d) DNA sequences for a ribosomal binding site and, optionally, DNA sequences for amino terminal amino acids such as, for example, the first 33 amino acids, of the bacteriophage lambda N protein. The vectors further contain a selective marker and a restriction site for cloning a foreign gene downstream from the P L promoter. |