Besse M, von Wilcken-Bergmann B, Müller-Hill B
EMBO J. 1986 Jun;5(6):1377-81. doi: 10.1002/j.1460-2075.1986.tb04370.x.
Plasmids were constructed which carry a synthetic lac operator at various distances from the lac promoter. They were tested in vivo for function in the presence and absence of lac repressor. We found significant repression when the lac operator is situated at the 3' end of the lac I gene or at the 5' end of the lac Z gene. When lac operators are inserted at both sites, we found a greater than 150-fold repression. The complex between lac repressor and DNA carrying these two lac operators is exceedingly stable in vitro suggesting that one tetrameric lac repressor may bind to both lac operators.
构建了一些质粒，这些质粒在距乳糖启动子不同距离处携带一个合成的乳糖操纵子。在有和没有乳糖阻遏物的情况下，对它们在体内的功能进行了测试。我们发现，当乳糖操纵子位于乳糖I基因的3'端或乳糖Z基因的5'端时，会有显著的阻遏作用。当在这两个位点都插入乳糖操纵子时，我们发现阻遏作用增加了150倍以上。乳糖阻遏物与携带这两个乳糖操纵子的DNA之间的复合物在体外极其稳定，这表明一个四聚体乳糖阻遏物可能会与两个乳糖操纵子结合。
