Plux, mutants with different promoting period and their application for quorum sensing regulated protein expression

Quorum sensing (QS) system can dynamically control the expression of proteins along with the cell growth. The promoting period of QS system has been little focused on until now. In this study, a self-induced dynamic regulated expression (SIDRE) system was constructed in Escherichia coli. To enable the system suitable for the expression of enzymes, promoter engineering was used to obtain Plux, mutants. To test the SIDRE system , alginate lyase AL493 and esterase Est7 were used as target protein for expression. The enzyme activity of alginate lyase and esterase reached 96.38% and 106.71% of the control strains containing the T7 promoter. In high-density fermentation, the activity of alginate lyase expressed by the SIDRE system with Plux,(T-38C) as promoter was 4.34-fold of that expressed by the T7 promoter. Therefore, the Plux, mutants with different promoting periods and/or different strengths show great potential in both laboratory and industrial scale for protein expression. (c) 2023 Beijing Academy of Food Sciences. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co., Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

A self-induced dynamic regulated expression system was constructed to efficiently express target proteins. The system showed 4.34-fold increase in enzyme activity compared to the traditional T7 promoter under high-density fermentation conditions. Therefore, the mutants with different promoters and/or strengths have great potential for protein expression.