Shang Fei, Wang Hui, Zhang Dan, Wang Wenhui, Yu Jiangliu, Xue Ting
Anhui Agricultural University, School of Life Sciences, Hefei, Anhui, China.
PeerJ. 2021 Nov 16;9:e12497. doi: 10.7717/peerj.12497. eCollection 2021.
The pET expression system based on T7 promoter which is induced by isopropyl-β-D-1-thiogalactopyranoside (IPTG) is by far the most commonly used system for production of heterogeneous proteins in . However, this system was limited by obvious drawbacks including the host toxicity and metabolic burden imposed by the presence of IPTG.
In this study, we incorporated the autoinducer-2 (AI-2) quorum sensing system to realize autoinduction of the pET expression system. The autoinduction expression vector pXWZ1 was constructed by inserting the promoter regions into the pET28a(+) vector. The expression efficiency of the reporter genes and by the pXWZ1 and pET28a(+) vectors were compared.
The results showed that the expression levels of the both report genes in the cells transformed with pXWZ1 without any addition of exogenous inducer were higher than that transformed with pET28a(+) vectors by the induction of IPTG.
This new auto-induction system will exclude the limitations of the IPTG induction including toxic to host and increasing formation of inclusion body and will become a more economical and convenient tool for recombinant protein expression.
基于T7启动子的pET表达系统由异丙基-β-D-1-硫代半乳糖苷（IPTG）诱导，是目前在大肠杆菌中生产异源蛋白最常用的系统。然而，该系统受到明显缺点的限制，包括IPTG的存在所带来的宿主毒性和代谢负担。
在本研究中，我们引入了自诱导物-2（AI-2）群体感应系统来实现pET表达系统的自诱导。通过将启动子区域插入pET28a(+)载体构建自诱导表达载体pXWZ1。比较了pXWZ1和pET28a(+)载体对报告基因和的表达效率。
结果表明，在不添加任何外源诱导剂的情况下，用pXWZ1转化的细胞中两个报告基因的表达水平高于用IPTG诱导的pET28a(+)载体转化的细胞。
这种新的自诱导系统将排除IPTG诱导的局限性，包括对宿主有毒和增加包涵体的形成，并将成为一种更经济、方便地用于重组蛋白表达的工具。
