Stable high copy number plasmids, their formation and use in protein production
    3.
    发明公开
    Stable high copy number plasmids, their formation and use in protein production 失效
    最好的蛋白质和蛋白质蛋白质。

    公开(公告)号:EP0013830A2

    公开(公告)日:1980-08-06

    申请号:EP79303035.4

    申请日:1979-12-21

    申请人: CETUS CORPORATION

    IPC分类号: C12N15/00 C12P21/00 C12P19/34

    CPC分类号: C12N15/69

    摘要: The problem of producing stable DNA plasmids of high copy number is solved by selecting mutants in which an altered repressor gene leads to high copy number replication. Translocatable elements in the plasmids are disabled in such a way that readthrough expression of heterologous DNA inserted in the plasmid will not continue into the translocatable elements or into elements which as a result of expression mediate rearrangement of said translocatable elements.
    Such plasmids may be used to produce a desired protein by introducing them into the genetic system of a host organism and permitting the organism to grow and phenotypically express its genotype.
    The invention also includes a method for removing 3' cutting restriction sites and maintaining 5' cutting restriction sites in DNA comprising cutting the DNA with appropriate restriction enzymes, treating the cut fragment with the enzyme DNA polymerase I in such a manner that 3' single stranded tails are removed and 5' single stranded tails are repaired to double stranded form, and blunt-end ligating the fragment to its previous orientation.

    摘要翻译: 通过选择其中改变的阻遏物基因导致高拷贝数复制的突变体来解决产生高拷贝数的稳定DNA质粒的问题。 质粒中的可转移元件被禁用,使得插入到质粒中的异源DNA的读取表达将不会继续进入可转运元件或由于表达介导所述可转位元件重排的元件。 这样的质粒可以用于通过将其引入宿主生物体的遗传系统中并且允许生物体生长并表型表达其基因型来产生所需的蛋白质。 本发明还包括一种去除3分钟切割限制位点并在DNA中保持5分钟切割限制性位点的方法,包括用合适的限制酶切割DNA,用酶DNA聚合酶I处理切割的片段,使得3分钟单链 尾部被去除,5分钟的单链尾巴被修复成双链形式,并且将末端连接到其先前的方向。