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bioRxiv · 10.1101/2023.05.08.539912

Remodeling the central metabolism of Escherichia coli enables a universal chassis

Liu, M.·Guo, L.·Huo, M.·Feng, X.·Zhao, Z.·Qi, Q.·Xian, M.·Zhao, G.
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Abstract

E. coli is the host of choice to produce a wide variety of chemicals and proteins. Overflow metabolism is considered as the widespread and major obstacle in microbial synthesis, and overcoming this common bottleneck may enable a universal chassis. Here, we constructed an E. coli universal chassis (ABKS strain) with significantly suppressed overflow metabolism, presenting similar growth rate, decreased glucose consumption, and increased production of desired chemicals and proteins when compared with wild-type BL21(DE3) strain. Furthermore, we demonstrated that metabolic flux of ABKS strain was reprogrammed from TCA cycle to glyoxylate bypass at isocitrate node via the synergistic effect of multi-layer regulation in gene transcription and protein modification. This metabolic reconfiguration alleviates overflow metabolism, avoids CO2 release in TCA cycle, finally improving the carbon atom economy in bioprocess. Our chassis has widespread and practical use for elevating the production and yield of multiple desired chemicals and proteins from different carbon source. The metabolic reconfiguration also provides theoretical basis for rational design of efficient bioproduction strains.

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Liu, M., Guo, L., Huo, M., Feng, X., Zhao, Z., Qi, Q., Xian, M., Zhao, G.. 2023-05-08. Remodeling the central metabolism of Escherichia coli enables a universal chassis. https://doi.org/10.1101/2023.05.08.539912

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