Balancing the non-linear rosmarinic acid biosynthetic pathway by modular co-culture engineering
Balancing the non-linear rosmarinic acid biosynthetic pathway by modular co-culture engineering
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DOI：
10.1016/j.ymben.2019.03.002
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发表时间：
2019-07-01
影响因子：
8.4
通讯作者：
Zhang, Haoran
中科院分区：
文献类型：
--
作者：
Li, Zhenghong;Wang, Xiaonan;Zhang, Haoran
途径平衡是利用代谢工程方法进行微生物生物合成的关键和常见挑战。非线性生物合成途径，如发散和收敛途径，对于生物生产优化是特别困难的，因为它们需要所有互连的组成途径模块之间的微妙平衡。模块化共培养工程的出现为生物合成途径的模块化和平衡提供了新的视角，因为单个途径模块的生物合成能力可以通过灵活调节携带指定模块的共培养菌株的亚群比例来协调。本研究开发了由多种代谢工程E.大肠杆菌菌株异源生物合成复杂的天然产物迷迭香酸（RA），其生物合成涉及复杂的发散-会聚途径。结果表明，与传统的单培养策略相比，工程双菌株共培养显著提高了RA的产量。在三菌株共培养的背景下进一步的途径模块化和平衡导致额外的生产改善。此外，利用不同的碳底物代谢工程共培养菌株招募，以提高三株共培养稳定性。基于这些努力的优化的共培养产生172 mg/L RA，表现出比用于单培养生物合成的亲本菌株生物合成提高38倍。这项工作的结果表明，模块化共培养工程的强大潜力，克服复杂的天然产物生物合成涉及非线性途径的挑战。
Pathway balancing is a critical and common challenge for microbial biosynthesis using metabolic engineering approaches. Non-linear biosynthetic pathways, such as diverging and converging pathways, are particularly difficult for bioproduction optimization, because they require delicate balancing between all interconnected constituent pathway modules. The emergence of modular co-culture engineering offers a new perspective for biosynthetic pathways modularization and balancing, as the biosynthetic capabilities of individual pathway modules can be coordinated by flexible adjustment of the subpopulation ratio of the co-culture strains carrying the designated modules. This study developed microbial co-cultures composed of multiple metabolically engineered E. coli strains for heterologous biosynthesis of complex natural product rosmarinic acid (RA) whose biosynthesis involves a complex diverging-converging pathway. Our results showed that, compared with the conventional mono-culture strategy, the engineered two-strain co-cultures significantly improved the RA production. Further pathway modularization and balancing in the context of three-strain co-cultures resulted in additional production improvement. Moreover, metabolically engineered co-culture strains utilizing different carbon substrates were recruited to improve the three-strain co-culture stability. The optimized co-culture based on these efforts produced 172 mg/L RA, exhibiting 38-fold biosynthesis improvement over the parent strain used in mono-culture biosynthesis. The findings of this work demonstrate the strong potentials of modular co-culture engineering for overcoming the challenges of complex natural product biosynthesis involving non-linear pathways.