| 摘要 |
PURPOSE:To provide a composite plasmid capable of using E.coli as a host, expressing cloned gene in high efficiency, and secreting the desired product from the cell of the host or to the periplasm. CONSTITUTION:The composite plasmid obtained by linking (A) the first DNA fragment containing the transcription promoter region of E.coli, (B) the second DNA fragment containing the promoter region of sak gene originated from Staphylococcus aureus and bonded to the downstream of the first fragment, the ribosome-linking site following the promoter region, the translation start codon following the site, and a region coding a signal peptide composed of 27 amino acids and positioned to the downstream side of the codon, and (C) the third DNA fragment for the insertion of heterologous gene, and having the sole restriction enzyme incision site in the whole region of DNA, and linked to the downstream side of the second fragment, to (D) the plasmid vector of E.coli. |
