A Universal Method for Developing Autoinduction Expression Systems Using AHL-Mediated Quorum-Sensing Circuits.

A major challenge in engineering microorganisms for the desirable product is maintaining the rational balance between cell growth and production. Quorum sensing (QS)-based dynamic regulations provide a pathway-independent genetic control technology to rebalance metabolic flux for biomass and product synthesis. However, the lack of a universal method for screening QS elements and the complex design of autoinduction circuits limit their applications in metabolic engineering. Here, we developed a universal method for simple and rapid screening and evaluating various QS systems from Gram-negative bacteria, and the largest library containing 195 combinations of receiving device/signal molecules was constructed and evaluated in . A simple logical circuit with different inducer synthesis rates was established to dynamically regulate gene expression levels, leading to efficient protein expression and product synthesis. The system was further applied in , which indicated it could be widely accommodated in other microorganisms. Therefore, the method could be used in diverse Gram-negative strains for the desired biosynthesis.