Danner D B
Gene. 1986;44(2-3):193-9. doi: 10.1016/0378-1119(86)90182-4.
To confer a detectable phenotype on any DNA fragment cloned in Escherichia coli, one can label the fragment by ligating it to the lac operator so that host cells can be identified as blue colonies on agar plates. This screening strategy is similar to that used for the pUC and M13 series of vectors, but does not require the vector to contain the lacZ gene. Instead, the presence of the lac operator on the multicopy vector results in the induction of the host cell beta-galactosidase by titrating out the repressor. This paper describes how pUC/M13 vectors or synthetic oligodeoxynucleotides can be used to supply the operator label, and shows how this method has been used to position unique restriction sites for initiating BAL 31 deletions. This approach may be particularly helpful when a given DNA fragment is to be cloned in many different constructs or is to pass through many sequential cloning steps.
为了使克隆在大肠杆菌中的任何DNA片段呈现可检测的表型，可以通过将其与lac操纵基因连接来标记该片段，这样宿主细胞在琼脂平板上就可以被鉴定为蓝色菌落。这种筛选策略与用于pUC和M13系列载体的策略相似，但不要求载体含有lacZ基因。相反，多拷贝载体上lac操纵基因的存在通过滴定阻遏物来诱导宿主细胞β-半乳糖苷酶。本文描述了如何使用pUC/M13载体或合成寡脱氧核苷酸来提供操纵基因标记，并展示了该方法如何用于定位启动BAL 31缺失的独特限制性酶切位点。当特定的DNA片段要克隆到许多不同的构建体中或要经过许多连续的克隆步骤时，这种方法可能特别有用。
