DNA synthesis by fragment assembly using extra-cellular DNA delivered by artificial controlled horizontal transfer

DNA synthesis in the Bacillus subtilis cells has become possible using extra-cellular DNA. Generally, purified DNAs in a test tube have been required to introduce into the host cells for molecular cloning technology in the laboratory. We have developed a cell lysis technique for natural transformation using stable extra-cellular plasmid DNAs, in which the extra-cellular plasmid DNAs are released from lysed Escherichia coli cells. DNA synthesis then proceeds by fragment assembly using the stable extracellular DNAs, without biochemical purification. DNA synthesis of the mouse mitochondrial genome in B. subtilis genome was illustrated using four E. coli strains with plasmid DNAs carrying contiguous DNA fragments. In the natural environment, unpurified extra-cellular DNAs contribute to the gene delivery during horizontal gene transfer (HGT). The technology introduced in the present study mimics HGT and should have a wide range of applications.