Cloning of L-2 DNA in Escherichia coli pOL4 plasmid

A physical map of L-2 DNA was constructed using restriction endonucleases. Based on this map the five HincII-generated L-2 DNA fragments (A-E) were cloned into the SmaI site of Escherichia coli vector plasmid pOL4, that was designed to analyze promoters and transcriptional terminators. The insertion of the HincII-generated L-2 DNA fragments into this plasmid clearly demonstrated that a fragment (fragment E) with a size of 1.1 kbp carried a sequence that initiated transcription in E. coli.