Duman-Özdamar Zeynep Efsun, Julsing Mattijs K, Martins Dos Santos Vitor A P, Hugenholtz Jeroen, Suarez-Diez Maria
Bioprocess Engineering, Wageningen University & Research, Wageningen, The Netherlands.
Laboratory of Systems and Synthetic Biology, Wageningen University & Research, Wageningen, The Netherlands.
Microb Biotechnol. 2025 Mar;18(3):e70089. doi: 10.1111/1751-7915.70089.
Extensive usage of plant-based oils, especially palm oil, has led to environmental and social issues, such as deforestation and loss of biodiversity, thus sustainable alternatives are required. Microbial oils, especially from Yarrowia lipolytica, offer a promising solution because of their similar composition to palm oil, low carbon footprint and ability to utilise low-cost substrates. In this study, we employed the Design-Build-Test-Learn (DBTL) approach to enhance lipid production in Y. lipolytica. We systematically evaluated predictions from the genome-scale metabolic model to identify and overcome bottlenecks in lipid biosynthesis. We tested the effect of predicted medium supplements (glutamate, leucine, methionine and threonine) and genetic intervention targets, including the overexpression of ATP-citrate lyase (ACL), acetyl-CoA carboxylase (ACC), threonine synthase (TS), diacylglycerol acyltransferase(DGA1), the deletion of citrate exporter gene (CEX1) and disruption of β-oxidation pathway (MFE1). This work revealed the critical roles of ACC, ACL, TS and DGA1 and the interaction of these genes with elevated intracellular citrate availability in lipid biosynthesis. Combining TS and DGA1 overexpression in the Δmfe_Δcex background achieved a remarkable 200% increase in lipid content (56% w/w) and a 230% increase in lipid yield on glycerol. These findings underscore the potential of Y. lipolytica as an efficient microbial cell factory for fatty acid production. Our study advances the understanding of lipid metabolism in Y. lipolytica and demonstrates a viable approach for developing sustainable and economically feasible alternatives to palm oil.
植物油尤其是棕榈油的广泛使用引发了环境和社会问题，如森林砍伐和生物多样性丧失，因此需要可持续的替代方案。微生物油脂，特别是解脂耶氏酵母产生的油脂，因其与棕榈油成分相似、碳足迹低以及能够利用低成本底物而提供了一个有前景的解决方案。在本研究中，我们采用设计-构建-测试-学习（DBTL）方法来提高解脂耶氏酵母中的脂质产量。我们系统地评估了基因组规模代谢模型的预测结果，以识别和克服脂质生物合成中的瓶颈。我们测试了预测的培养基补充物（谷氨酸、亮氨酸、蛋氨酸和苏氨酸）和基因干预靶点的效果，包括ATP-柠檬酸裂解酶（ACL）、乙酰辅酶A羧化酶（ACC）、苏氨酸合酶（TS）、二酰基甘油酰基转移酶（DGA1）的过表达，柠檬酸输出基因（CEX1）的缺失以及β-氧化途径的破坏（MFE1）。这项工作揭示了ACC、ACL、TS和DGA1的关键作用以及这些基因与细胞内柠檬酸可用性升高在脂质生物合成中的相互作用。在Δmfe_Δcex背景下将TS和DGA1过表达相结合，脂质含量显著增加了200%（56% w/w），甘油上的脂质产量增加了230%。这些发现强调了解脂耶氏酵母作为脂肪酸生产高效微生物细胞工厂的潜力。我们的研究增进了对解脂耶氏酵母脂质代谢的理解，并展示了一种开发可持续且经济可行的棕榈油替代品的可行方法。
