pET-17b质粒是一种原核表达载体,N端含有一个T7标签。该质粒含有多个常用的酶切位点,便于不同基因克隆。表达由宿主细胞提供的T7 RNA聚合酶诱导,目的基因被克隆到质粒载体上,受噬菌体强转录及翻译信号控制。
pET系统是有史以来在大肠杆菌中表达重组蛋白的功能最强大的系统,也是现今原核表达方面使用最广泛的系统。该系列质粒能很容易的通过降低诱导物的浓度来削弱蛋白表达。在非诱导条件下,可以使目的基因处于完全沉默状态而不转录。
The pET-17b vector carries an N-terminal 11aa T7?Tag? sequence followed by a region of useful cloning sites. Included in the multiple cloning region are dual BstX I sites, which allow efficient cloning using an asymmetric linker. Unique sites (except for the two BstX I sites) are shown on the circle map. Note that the sequence is numbered by the pBR322 convention, so the T7 expression region is reversed on the circluar map. The cloning/expression region of the coding strand transcribed by T7 RNA polymerase is shown below.