Dong Tianyu, Zhou Xiao, Hou Zheng-Jie, Shu Yujie, Yao Mingdong, Liu Zhi-Hua, Cheng Jing-Sheng, Xiao Wenhai, Wang Ying
Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China.
Frontier Research Institute for Synthetic Biology, Tianjin University, Tianjin 300072, China.
J Agric Food Chem. 2025 Jan 8;73(1):693-705. doi: 10.1021/acs.jafc.4c09552. Epub 2024 Dec 19.
7-Dehydrocholesterol (7-DHC) is an important precursor of vitamin D. The microbial synthesis of 7-DHC has attracted substantial attention. In this study, multiple strategies were developed to create a sustainable green route for enhancing 7-DHC yield from kitchen waste by engineered . strains were engineered and combined with various Δ-dehydrocholesterol reductases. Overexpressing all the genes in the mevalonate pathway improved the precursor pool, increasing the 7-DHC titer from 21.8 to 145.6 mg/L. Additionally, optimizing medium components using the response surface method significantly raised the 7-DHC titer to 391.0 mg/L after shake flask cultivation. The engineered strain yielded a record 7-DHC titer of 3.5 g/L in a 5-L bioreactor when kitchen waste was used as a carbon source. Overall, these results demonstrate that engineered efficiently synthesizes 7-DHC from waste lipid feedstock, offering a promising route for its bioproduction.
7-脱氢胆固醇（7-DHC）是维生素D的重要前体。7-DHC的微生物合成已引起广泛关注。在本研究中，开发了多种策略，以创建一条可持续的绿色途径，通过工程菌株提高厨余垃圾中7-DHC的产量。对菌株进行了工程改造，并与各种Δ-脱氢胆固醇还原酶相结合。甲羟戊酸途径中所有基因的过表达改善了前体库，使7-DHC滴度从21.8毫克/升提高到145.6毫克/升。此外，使用响应面法优化培养基成分，摇瓶培养后7-DHC滴度显著提高到391.0毫克/升。当使用厨余垃圾作为碳源时，该工程菌株在5升生物反应器中产生了创纪录的3.5克/升的7-DHC滴度。总体而言，这些结果表明，工程菌株能有效地从废弃脂质原料中合成7-DHC，为其生物生产提供了一条有前景的途径。
