Increasing the robustness of Escherichia coli for aromatic chemicals production through transcription factor engineering.

Engineering microbial cell factories has been widely used to produce a variety of chemicals, including natural products, biofuels, and bulk chemicals. However, poor robustness limits microbial production on an industrial scale. Microbial robustness is essential to ensure reliable and sustainable production of targeted chemicals. In this study, we developed an approach to screen transcription factors to improve robustness using CRSPRa technology. We applied this approach to identify some transcription factors to increase the robustness of Escherichia coli to aromatic chemicals. Activation of hdfR, yldP, purR, sosS, ygeH, cueR, cra, and treR increased the robustness of E. coli to phenyllactic acid. Upregulation of some transcription factors also improved the robustness to caffeic acid (cra) or tyrosol (cra, cueR, treR, soxS, hdfR and purR). Our study demonstrated that transcription factor engineering using CRISPRa is a powerful method to increase microbial robustness. This research provides new approaches to efficiently find genes responsible for increasing microbial robustness.