基于能量代谢分析的S-腺苷蛋氨酸和谷胱甘肽联合高产方法

Strategy for enhanced co-production of S-adenosylmethionine and glutathione by Candida utilis based on energy metabolic analysis

采用能量代谢分析方法,以S-腺苷蛋氨酸和谷胱甘肽联产发酵过程中能量代谢的关键物质ATP的水平变化为指导,结合L-半胱氨酸的适时添加策略,实现了S-腺苷蛋氨酸和谷胱甘肽联产发酵的进一步高产。在ATP水平指导的L-半胱氨酸添加策略下,实现了胞内ATP的有效利用,且分批培养和流加培养时S-腺苷蛋氨酸和谷胱甘肽的联产量达到584.7mg.L-1和1004.4mg.L-1,分别比对照提高了27.1%和26.4%。该研究结果为类似耗能合成有用化学品的联产发酵及其高产提供了可行的发酵过程优化策略。

The concentrations of intracellular co-factors,such as ATP,ADP,NADH and NAD＋ vital for energy metabolism within Candida utilis CCTCC M 209298 were measured by HPLC.Based on the levels of co-factors,especially ATP during batch cultivation of C.utilis CCTCC M 209298,we developed a novel culture strategy of L-cysteine addition followed by ATP accumulation（21 h） instead of cell growth ceased（15 h） for further enhanced co-production of S-adenosylmethionine and glutathione using energy metabolic analysis.Subsequently,we combined this strategy with high-cell-density culture of C.utilis CCTCC M 209298,and both high biomass and high co-production of S-adenosylmethionine and glutathione were achieved.The culture strategy under the guidance of ATP concentration was proved to be efficient in terms of full utilization of intracellular residual ATP,together with improvement of co-production of S-adenosylmethionine and glutathione,and the co-production of S-adenosylmethionine and glutathione attained 584.7 mg·L-1 and 1004.4 mg·L-1 from batch and fed-batch fermentation,which were 27.1% and 26.4% higher than the controls,respectively.The results presented in this study provide a feasible strategy for optimization of fermentative processes for enhancing the co-production of analogous useful chemicals biosynthesized by consuming energy.