Zhu Yunqi, Zhao Mingli, Wang Hao, Zhu Yingying, Mu Wanmeng
School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, 214122, China.
Bloomage Biotechnology Corp., Ltd., Jinan, Shandong 250010, China.
Bioresour Technol. 2025 Mar;419:132062. doi: 10.1016/j.biortech.2025.132062. Epub 2025 Jan 18.
2'-Fucosyllactose (2'-FL) is the most abundant human milk oligosaccharide (HMO) and has been approved to be commercially added to infant formula. Microbial synthesis from exogenous lactose via metabolic engineering is currently the major approach to production of 2'-FL. Replacement of lactose with cheaper sugars such as glucose and sucrose has been studied to reduce the production costs. Herein, Escherichia coli BL21(DE3) was engineered to produce 2'-FL by co-culture with glucose and xylose, the main components of lignocellulosic biomass. Firstly, synthetic pathway of lactose from xylose and glucose was constructed by introducing a lactose-forming enzyme, strengthening xylose uptake pathway, and weakening glucose metabolic pathway. Then, a highly-active α1,2-fucosyltransferase BKHT was introduced to produce 2'-FL and GDP-fucose supply was enhanced to increase 2'-FL production. As a result, when cocultured with glucose and xylose, the engineered strain produced 6.53 g/L and 27.53 g/L of 2'-FL by shake-flask and fed-batch cultivation, respectively.
2'-岩藻糖基乳糖（2'-FL）是最丰富的人乳寡糖（HMO），已被批准可商业添加到婴儿配方奶粉中。目前，通过代谢工程从外源乳糖进行微生物合成是生产2'-FL的主要方法。人们已经研究了用葡萄糖和蔗糖等更便宜的糖替代乳糖以降低生产成本。在此，对大肠杆菌BL21(DE3)进行工程改造，使其与木质纤维素生物质的主要成分葡萄糖和木糖共培养来生产2'-FL。首先，通过引入乳糖形成酶、强化木糖摄取途径和弱化葡萄糖代谢途径，构建了从木糖和葡萄糖合成乳糖的途径。然后，引入高活性的α1,2-岩藻糖基转移酶BKHT来生产2'-FL，并增强GDP-岩藻糖供应以提高2'-FL产量。结果，当与葡萄糖和木糖共培养时，该工程菌株通过摇瓶培养和分批补料培养分别产生了6.53 g/L和27.53 g/L的2'-FL。
