Zou Shu-Ping, Zhao Kuo, Wang Zhi-Jian, Zhang Bo, Liu Zhi-Qiang, Zheng Yu-Guo
The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou, 310014 People's Republic of China.
Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310014 People's Republic of China.
3 Biotech. 2021 Jun;11(6):295. doi: 10.1007/s13205-021-02773-0. Epub 2021 May 24.
D-pantothenic acid (D-PA), as a crucial vitamin, is widely used in food, animal feed, cosmetics, and pharmaceutical industries. In our previous work, recombinant W3110 for production of D-PA was constructed through metabolic pathway modification. In this study, to enhance D-PA production, statistical optimization techniques including Plackett-Burman (PB) design and Box-Behnken design (BBD) first were adopted to optimize the culture condition. The results showed that the glucose, β-alanine and (NH)SO have the most significant effects on D-PA biosynthesis. The response surface model based on BBD predicted that the optimal concentration is glucose 56.0 g/L, β-alanine 2.25 g/L and (NH4)SO 11.8 g/L, the D-PA titer increases from 3.2 g/L to 6.73 g/L shake flask fermentation. For the fed-batch fermentation in 5 L fermenter, the isoleucine feeding strategy greatly increased the titer and productivity of D-PA. As a result, titer (31.6 g/L) and productivity (13.2 g/L·d) of D-PA were achieved, they increased by 4.66 times and 2.65 times, respectively, compared with batch culture. At the same time, the accumulation of acetate reduced from 29.79 g/L to 8.55 g/L in the fed-batch fermentation. These results demonstrated that the optimization of medium composition and the cell growth rate are important to increase the concentration of D-PA for microbial fermentation. This work laid the foundation for further research on the application of D-PA microbial synthesis.
The online version contains supplementary material available at 10.1007/s13205-021-02773-0.
D-泛酸（D-PA）作为一种关键维生素，广泛应用于食品、动物饲料、化妆品和制药行业。在我们之前的工作中，通过代谢途径改造构建了用于生产D-PA的重组W3110。在本研究中，为提高D-PA产量，首先采用包括Plackett-Burman（PB）设计和Box-Behnken设计（BBD）在内的统计优化技术来优化培养条件。结果表明，葡萄糖、β-丙氨酸和硫酸铵对D-PA生物合成影响最为显著。基于BBD的响应面模型预测，最佳浓度为葡萄糖56.0 g/L、β-丙氨酸2.25 g/L和硫酸铵11.8 g/L，摇瓶发酵时D-PA效价从3.2 g/L提高到6.73 g/L。对于5 L发酵罐中的补料分批发酵，异亮氨酸补料策略极大地提高了D-PA的效价和生产率。结果，D-PA的效价（31.6 g/L）和生产率（13.2 g/L·d）得以实现，与分批培养相比，分别提高了4.66倍和2.65倍。同时，补料分批发酵中乙酸的积累从29.79 g/L降至8.55 g/L。这些结果表明，优化培养基组成和细胞生长速率对于提高微生物发酵中D-PA的浓度很重要。这项工作为D-PA微生物合成应用的进一步研究奠定了基础。
在线版本包含可在10.1007/s13205-021-02773-0获取的补充材料。
