School of Chemical Engineering and Technology, Tianjin University, Tianjin, PR China.
Frontiers Science Center for Synthetic Biology, Tianjin University, Tianjin, PR China.
Biotechnol J. 2024 Feb;19(2):e2300383. doi: 10.1002/biot.202300383.
Synthetic biology-based engineering of Saccharomyces cerevisiae to produce terpenoid natural products is an effective strategy for their industrial application. Previously, we observed that glycerol addition was beneficial for ginsenoside compound K (CK) production in a S. cerevisiae when it was fermented using the YPD medium. Here, we reconstructed the CK synthesis and glycerol catabolic pathway in a high-yield protopanaxadiol (PPD) S. cerevisiae strain. Remarkably, our engineered strain exhibited the ability to utilize glycerol as the sole carbon source, resulting in a significantly enhanced production of 433.1 ± 8.3 mg L of CK, which was 2.4 times higher compared to that obtained in glucose medium. Transcriptomic analysis revealed that the transcript levels of several key genes involved in the mevalonate (MVA) pathway and the uridine diphosphate glucose (UDPG) synthesis pathway were up-regulated in response to glycerol. The addition of glycerol enhanced CK titers by augmenting the flux of the terpene synthesis pathway and facilitating the production of glycosyl donors. These results suggest that glycerol is a promising carbon source in S. cerevisiae, especially for the production of triterpenoid saponins.
基于合成生物学的酿酒酵母工程改造生产萜类天然产物是其工业应用的有效策略。以前，当我们用 YPD 培养基发酵时，我们观察到添加甘油有利于在酿酒酵母中生产人参皂苷化合物 K（CK）。在这里，我们在高产原人参二醇（PPD）酿酒酵母菌株中重建了 CK 合成和甘油分解代谢途径。值得注意的是，我们的工程菌株能够利用甘油作为唯一的碳源，导致 CK 的产量显著提高，达到 433.1 ± 8.3 mg/L，比在葡萄糖培养基中获得的产量高 2.4 倍。转录组分析表明，参与甲羟戊酸（MVA）途径和尿苷二磷酸葡萄糖（UDPG）合成途径的几个关键基因的转录水平随着甘油的添加而上调。甘油的添加通过增加萜烯合成途径的通量并促进糖基供体的产生来提高 CK 的产量。这些结果表明，甘油是酿酒酵母中一种有前途的碳源，特别是对于三萜皂苷的生产。
