Selvaratnam S, Gealt M A
Department of Bioscience and Biotechnology, Drexel University, Philadelphia, Pennsylvania 19104.
J Bacteriol. 1993 Nov;175(21):6982-7. doi: 10.1128/jb.175.21.6982-6987.1993.
Although nonconjugative mobilizable plasmids require helping functions of conjugative plasmids in order to be mobilized into recipients, at least some genes from the nonconjugative plasmids may be induced to assist in the DNA transfer process. Conjugative plasmids from 12 different incompatibility groups mobilized the nonconjugative plasmid ColE1Ap between Escherichia coli strains. Introduction of any of the conjugative plasmids into the ColE1Ap-containing strain resulted in an induction of mbeC, the product of which is a component of the mobilization relaxation complex. Each of the conjugative plasmids caused protein to bind specifically to mbe promoter DNA, suggesting a direct regulatory interaction.
虽然非接合型可移动质粒需要接合型质粒的辅助功能才能被转移到受体细胞中，但至少非接合型质粒的一些基因可能会被诱导来协助DNA转移过程。来自12个不同不相容群的接合型质粒在大肠杆菌菌株之间转移了非接合型质粒ColE1Ap。将任何一种接合型质粒导入含有ColE1Ap的菌株都会诱导mbeC的表达，其产物是转移松弛复合体的一个组成部分。每种接合型质粒都会使蛋白质特异性地结合到mbe启动子DNA上，这表明存在直接的调控相互作用。
