[Supercopy plasmid based on the replicon from the temperate N15 bacteriophage].Mol Gen Mikrobiol Virusol. 1994 Jan-FebMG
Mini-plasmids, based on the N15 temperate bacteriophage replicon, are described. One of these, N15-203 linear 13.8 kb plasmid, has anomalously high copy number--more than 250 per one bacterial chromosome and the amount of plasmid DNA comprises about half of the total DNA of a cell. This property of N15-203 plasmid is realized only in the strain lysogenic for a N15 phage and is lost for the circular deletion versions of N15-203. The efficiency of transformation of E. coli C (N15) strain is essentially the same for N15-203 and pUC4K plasmids. Insertion of foreign DNA with a size up to 20 kb into BgIII cloning site of N15-203 plasmid does not decrease significantly efficiency of transformation calculated per number of DNA molecules and the total amount of plasmid DNA in a cell. N15-203 plasmid may be used as a vector for molecular cloning of relatively large DNA fragments, and in those biotechnology processes when productivity depends on a vector's copy number.