The plasmid of this invention contains the cII translation initiation site and a PL promoter-both are very efficient, producing large amounts of cII protein. This plasmid contains a unique ClaI restriction site in the aminoterminal portion of the cII gene suitable for insertion of foreign genes. This plasmid is an improvement over other plasmids because the inserted genes are subject to the same transcriptional and translational characteristics of the cII gene; this plasmid, therefore, produces large amounts of the protein coded by the exogenous gene.
