代谢工程改造马克斯克鲁维酵母生产琥珀酸

Metabolic Engineering of Kluyveromyces marxianus for Succinic Acid Production

摘要:

【目的】 构建琥珀酸生物合成细胞工厂，实现琥珀酸的高效合成。【方法】以马克斯克鲁维酵母（Kluyveromyces marxianus，K. marxianus）为底盘菌株，通过代谢工程策略，包括阻断副产物合成路径、强化糖酵解途径、构建异源琥珀酸合成途径、优化关键酶表达量、 增强琥珀酸跨膜转运能力等，构建了生物合成琥珀酸的酵母工程菌株。最后，通过发酵工艺优化提高其生产能力。【结果】在5 L发酵罐上，工程菌株K. marxianus SA011的琥珀酸产量、得率和生产强度分别达到了10.06 g/L、11.4%和0.15 g/（L·h）。【结论】该研究为K. marxianus的代谢工程改造提供了新思路，也为利用酵母高效生物合成琥珀酸及其工业化应用奠定了重要基础。

Abstract:

[Objective] This study constructed a succinic acid-producing cell factory for the efficient biosynthesis of succinic acid. [Method] Using Kluyveromyces marxianus (K. marxianus) as the chassis strain, an engineered yeast strain for the biosynthesis of succinic acid through comprehensive metabolic engineering strategies was constructed. These strategies encompassed the disruption of by-product synthesis pathways, enhancement of glycolytic flux, introduction of a heterologous succinic acid biosynthetic pathway, optimization of key enzyme expression, and augmentation of transmembrane transport of succinic acid. Finally, a fermentation process optimization was performed to improve the production performance. [Result] The engineered strain K. marxianus SA011 achieved a succinic acid titer of 10.06 g/L, a yield of 11.4%, and a productivity of 0.14 g/(L·h) in a 5 L bioreactor. [Conclusion] This study provides new insights into the metabolic engineering of K. marxianus and establishes a foundation for the efficient biosynthesis of succinic acid by yeast, facilitating its industrial application.