Details

Autor(en) / Beteiligte

• Song, Jie
• Zhuang, Miaomiao
• Fang, Yu
• Hu, Xiaoqing
• Wang, Xiaoyuan

Titel

Self-regulated efficient production of L-threonine via an artificial quorum sensing system in engineered Escherichia coli

Ist Teil von

• Microbiological research, 2024-07, Vol.284, p.127720-127720, Article 127720

Ort / Verlag

Germany: Elsevier GmbH

Erscheinungsjahr

2024

Quelle

MEDLINE

Beschreibungen/Notizen

• Imbalance in carbon flux distribution is one of the most important factors affecting the further increase in the yield of high value-added natural products in microbial metabolic engineering. Meanwhile, the most common inducible expression systems are difficult to achieve industrial-scale production due to the addition of high-cost or toxic inducers during the fermentation process. Quorum sensing system, as a typical model for density-dependent induction of gene expression, has been widely applied in synthetic biology. However, there are currently few reports for efficient production of microbial natural products by using quorum sensing system to self-regulate carbon flux distribution. Here, we designed an artificial quorum sensing system to achieve efficient production of L-threonine in engineered Escherichia coli by altering the carbon flux distribution of the central metabolic pathways at specific periods. Under the combination of switch module and production module, the system was applied to divide the microbial fermentation process into two stages including growth and production, and improve the production of L-threonine by self-inducing the expression of pyruvate carboxylase and threonine extracellular transporter protease after a sufficient amount of cell growth. The final strain TWF106/pST1011, pST1042pr could produce 118.2 g/L L-threonine with a yield of 0.57 g/g glucose and a productivity of 2.46 g/(L· h). The establishment of this system has important guidance and application value for the production of other high value-added chemicals in microorganisms by self-regulation. [Display omitted] •Designed and optimized an artificial quorum sensing system in Escherichia coli.•Redistributed the carbon flux by the overexpression of pyc in E. coli.•Improved the yield of L-threonine by self-induced expression of rhtC.•The final E. coli strain constructed in this study produced 118.2 g/L L-threonine.