Backman K, Ptashne M
Cell. 1978 Jan;13(1):65-71. doi: 10.1016/0092-8674(78)90138-1.
Recombination in vitro has been used to place one or more copies of a strong promoter, the lac promoter, at varying distances from the cl (repressor) gene of bacteriophage lambda on the E. coli plasmid pMB9. In all constructions, lambda repressor synthesis is driven wholly or predominantly by the inserted lac promoter. One of our fusions directs the synthesis of very high levels of lambda repressor. In this case, the fused DNA encodes a ribosome binding site which is a "hybrid" of lambda and lac sequences. In principle, this method of construction should elicit high levels of expression in E. coli of any gene, whatever its source. We also described strains with different sequence arrangements that, for reasons not completely understood, produce less repressor.
体外重组已被用于将一个或多个强启动子（即乳糖启动子）的拷贝，以不同的距离置于大肠杆菌质粒pMB9上噬菌体λ的cl（阻遏物）基因处。在所有构建体中，λ阻遏物的合成完全或主要由插入的乳糖启动子驱动。我们构建了一种融合体，它能指导合成非常高水平的λ阻遏物。在这种情况下，融合的DNA编码一个核糖体结合位点，它是λ和乳糖序列的“杂交体”。原则上，这种构建方法应该能在大肠杆菌中高水平表达任何基因，无论其来源如何。我们还描述了具有不同序列排列的菌株，由于尚未完全理解的原因，但它们产生的阻遏物较少。
