毒素蛋白CcdB在载体构建中的研究及应用

大肠杆菌毒素-抗毒素系统ccd(control of cell division or death system)编码的毒素蛋白CcdB使细胞内DNA促旋酶失活,杀伤宿主细胞,而抗毒素蛋白CcdA可以中和毒素CcdB使宿主存活。利用这个原理,CcdB可作为细菌转化时的筛选标记,在构建各种高效低背景载体上发挥重要作用。我们简要综述毒素蛋白CcdB的毒性原理及其在质粒载体构建中的广泛应用。

Research and Application of Toxin Protein CcdB in the Construc tion of Various Vectors

CcdB is the toxin component of control of cell division or death system（ccd system） in Escherichia coli, and it can poison gyrase and lead to cell death. CcdA protein, the antitoxin of ccd system, interacts with CcdB to neutralize its toxicity. According to this mechanism, CcdB can be used as a positive-selection marker dur ing transformation and picking of colonies, which play a major role in the construction of high efficient zero-back ground vectors. In this paper we mainly discussed about the toxin of CcdB and its wide use in the construction of various vectors.