文献类型：期刊文献

英文题名：Engineering Escherichia coli for High-Yield Protoporphyrin IX Biosynthesis via Cytotoxicity Mitigation and Pathway Optimization

作者：Sun, Peng[1];Qian, Lin-Lin[1];Xie, Wen-Liang[1];Jiang, Yao[1];Li, Chun-Xiu[1,2];Pan, Jiang[1,2];Xu, Jian-He[1,2]

机构：[1]East China Univ Sci & Technol, Lab Biocatalysis & Synthet Biotechnol, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China;[2]East China Univ Sci & Technol, Shanghai Collaborat Innovat Ctr Biomfg, Sch Biotechnol, Shanghai 200237, Peoples R China

年份：2025

卷号：14

期号：11

起止页码：4400

外文期刊名：ACS SYNTHETIC BIOLOGY

收录：;WOS:【SCI-EXPANDED(收录号:WOS:001601184300001)】；

基金：This work was financially supported by the National Natural Science Foundation of China (22478116 and 32471495), the National Key R & D Program of China (2024YFA0917800), and the Fundamental Research Funds for the Central Universities (22221818014).

语种：英文

外文关键词：protoporphyrin IX; 5-aminolevulinic acid; heme; metabolic engineering; synthetic sRNA; Escherichia coli

摘要：Porphyrins are essential tetrapyrroles that play critical roles in biological electron-transfer and light-harvesting systems. As the universal precursor of heme and chlorophyll, protoporphyrin IX (PP IX) has transformative potential for fields as diverse as biomedicine, materials, food, and agriculture. However, large-scale microbial PP IX production is subject to challenges regarding cellular toxicity and regulation of tetrapyrrole biosynthesis. Herein, we report a synthetic-biology-driven Escherichia coli platform enabled by spatially resolved pathway optimization and cytotoxicity mitigation. By introducing a hyperactive 5-aminolevulinic acid synthase and rebalancing branch pathways via sRNA-based knockdown, we decoupled the PP IX synthesis from endogenous regulatory constraints. Integration of the MacAB-TolC efflux system reduced intracellular PP IX accumulation by 16%, synergistically enhancing extracellular productivity. PP IX titer values of 3.90 g/L and 65.0 mg/L/h productivity were achieved in a 5 L bioreactor, the highest ever reported. The engineered chassis exhibits metabolic plasticity, coproducing 0.24 g/L heme through dynamic pathway modifications. This work establishes a new paradigm for cytotoxic metabolite synthesis through spatiotemporal pathway governance, circumventing classical toxicity-productivity trade-offs. Our work establishes an efficient platform for microbial PP IX production. Furthermore, the engineered chassis developed here enables versatile applications in next-generation porphyrin biomanufacturing.