School of Biotechnology and Key Laboratory of Industrial Biotechnology of Ministry of Education, Jiangnan University, Wuxi 214122, China.
J Agric Food Chem. 2024 Oct 23;72(42):23411-23421. doi: 10.1021/acs.jafc.4c07423. Epub 2024 Oct 8.
Raspberry ketone (RK), a natural product derived from raspberry fruit, is commonly utilized as a flavoring agent in foods and as an active component for weight loss. Metabolic engineering has enabled microorganisms to produce RK more efficiently and cost-effectively. However, the biosynthesis of RK is hindered by an unbalanced synthetic pathway and a deficiency of precursors, including tyrosine and malonyl-CoA. In this study, we constructed and optimized the RK synthetic pathway in using a static metabolic engineering strategy to enhance the biosynthesis of tyrosine from glucose, thereby achieving the production of RK. Additionally, the synthetic and consumption pathways of malonyl-CoA were dynamically regulated by -coumaric acid-responsive biosensor to balance the metabolic flux distribution between cell growth and RK biosynthesis. Following pathway optimization, the medium components and fermentation conditions were further refined, resulting in a significant increase in the RK titer to 415.56 mg/L. The optimized strain demonstrated a 32.4-fold increase in the RK titer while maintaining a comparable final OD to the initial strain. Overall, the implemented static and dynamic regulatory strategies provide a novel approach for the efficient production of RK, taking into account cell viability and growth.
覆盆子酮（RK）是一种天然产物，来源于覆盆子果实，通常用作食品的调味剂和减肥的活性成分。代谢工程使微生物能够更高效、更经济地生产 RK。然而，RK 的生物合成受到不平衡的合成途径和前体（包括酪氨酸和丙二酰辅酶 A）缺乏的限制。在这项研究中，我们使用静态代谢工程策略在 中构建和优化了 RK 合成途径，以增强葡萄糖向酪氨酸的生物合成，从而实现了 RK 的生产。此外，通过对香豆酸响应生物传感器对丙二酰辅酶 A 的合成和消耗途径进行动态调控，平衡细胞生长和 RK 生物合成之间的代谢通量分配。在途径优化之后，进一步优化了培养基成分和发酵条件，使 RK 的产量显著提高到 415.56mg/L。优化后的菌株在保持与初始菌株相当的最终 OD 的情况下，RK 的产量提高了 32.4 倍。总的来说，所实施的静态和动态调控策略为 RK 的高效生产提供了一种新方法，同时考虑到了细胞活力和生长。
