| 摘要 |
PURPOSE:To provide a plasmid separated from glutamin-producing coryneform bacteria, giving a large number of copies in the cell, and useful in the DNA recombination technology to which a remarkable gene amplification is expected when recombinated with exogenotes. CONSTITUTION:A plasmid having a molecular weight of 3.0+ or -0.1 megadalton and separated from glutamine-producing coryneform bacteria. For example, Brevibacterium lactofermentum ATCC 13869 is inoculated in CMG medium, cultured at 30 deg.C until the latter half of the logarithmic phase, subjected to bacteriolysis, and separatd by ultracentrifugation at 30,000Xg for 30min to obtain a supernatant liquid. Polyethylene glycol is added to the liquid to precipitate and concentrate plasmid DNA, which is purified by agarose gel electrophoresis to obtain the objective plasmid pAM 330. When Corynebacterium glutamicum AJ 11560 (FERM-P No.5485) is used as the coryneform bacteria, the product is plasmid pAM 286. It is suitable as a vector using glutamine-producing coryneform bacteria as the host. |
