Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96, Gothenburg, SE, Sweden.
Department of Pharmaceutical Microbiology, Faculty of Pharmacy, Anadolu University, Eskisehir, 26471, Turkey.
Microb Cell Fact. 2024 Sep 6;23(1):241. doi: 10.1186/s12934-024-02512-z.
Metabolic engineering enables the sustainable and cost-efficient production of complex chemicals. Efficient production of terpenes in Saccharomyces cerevisiae can be achieved by recruiting an intermediate of the mevalonate pathway. The present study aimed to evaluate the engineering strategies of S. cerevisiae for the production of taxadiene, a precursor of taxol, an antineoplastic drug.
SCIGS22a, a previously engineered strain with modifications in the mevalonate pathway (MVA), was used as a background strain. This strain was engineered to enable a high flux towards farnesyl diphosphate (FPP) and the availability of NADPH. The strain MVA was generated from SCIGS22a by overexpressing all mevalonate pathway genes. Combining the background strains with 16 different episomal plasmids, which included the combination of 4 genes: tHMGR (3-hydroxy-3-methylglutaryl-CoA reductase), ERG20 (farnesyl pyrophosphate synthase), GGPPS (geranyl diphosphate synthase) and TS (taxadiene synthase) resulted in the highest taxadiene production in S. cerevisiae of 528 mg/L.
Our study highlights the critical role of pathway balance in metabolic engineering, mainly when dealing with toxic molecules like taxadiene. We achieved significant improvements in taxadiene production by employing a combinatorial approach and focusing on balancing the downstream and upstream pathways. These findings emphasize the importance of minor gene expression modification levels to achieve a well-balanced pathway, ultimately leading to enhanced taxadiene accumulation.
代谢工程使复杂化学物质的可持续和经济高效生产成为可能。通过招募甲羟戊酸途径的中间产物，可以在酿酒酵母中高效生产萜类化合物。本研究旨在评估酿酒酵母生产紫杉烷（紫杉醇的前体，一种抗癌药物）前体紫杉二烯的工程策略。
SCIGS22a 是一种经过修饰的甲羟戊酸途径（MVA）工程菌株，用作背景菌株。该菌株经过工程改造，使法尼基二磷酸（FPP）和 NADPH 的通量增加。MVA 菌株是通过在 SCIGS22a 中过表达所有甲羟戊酸途径基因而产生的。将背景菌株与 16 种不同的附加质粒组合，其中包括 4 种基因的组合：tHMGR（3-羟-3-甲基戊二酰辅酶 A 还原酶）、ERG20（法尼基焦磷酸合酶）、GGPPS（香叶基二磷酸合酶）和 TS（紫杉二烯合酶），导致酿酒酵母中紫杉二烯的产量最高达到 528mg/L。
我们的研究强调了代谢工程中途径平衡的关键作用，特别是在处理紫杉二烯等有毒分子时。我们通过采用组合方法并专注于平衡上下游途径，实现了紫杉二烯产量的显著提高。这些发现强调了小基因表达修饰水平对实现平衡途径的重要性，最终导致紫杉二烯的积累增加。
