基于途径分析的L-异亮氨酸发酵溶氧控制研究  

Study of L-Isoleucine Fermentation Oxygen Controlling on the Basis of Pathway Analysis

作　　者：杨宁[1] 王健[2] 徐庆阳[1] 陈宁[1] 温廷益[1] 

机构地区：[1]天津科技大学生物工程学院,天津300222 [2]吉林大学生物与农业工程学院,长春130022

出　　处：《中国生物工程杂志》2007年第2期70-75,共6页China Biotechnology

基　　金：天津市科技攻关项目(05YFGPGX07000)

摘　　要：利用途径分析方法对黄色短杆菌(Brevibacterium flavum)TC-21生产L-异亮氨酸的途径进行了分析,确定了黄色短杆菌TC-21生产L-异亮氨酸的最佳途径的通量分布,根据途径分析的结果,发酵过程中的代谢流量对L-异亮氨酸产量有明显影响,而代谢流量与发酵过程中的溶氧密切相关,因此可以通过控制溶氧来提高L-异亮氨酸产量。在发酵过程的不同阶段,根据菌体生长和产酸的需求,改变合成途径的代谢流量,可以有效提高产酸率。实验证明,通过溶氧分阶段控制发酵生产L-异亮氨酸,比溶氧恒定控制方式发酵产率提高了15.77%。实验结果说明,用途径分析的结果指导发酵过程中的溶氧可以大幅度提高L-异亮氨酸的产量。Pathway analysis, the theoretical basis for gene operation and elementary method for metabolic network analysis ,was conducted for production of L-isoleucine by Brevibacterium flavum TC-21. Metrology mode and some professional program were used in pathway analysis to establish the best metabolic mode of L- isoleucine. Metabolic engineering is used to restructure the metabolic flux in some pathways or to redirect the flux distributions in different pathways, and its target is to trim the primary metabolism to introduce the metabolic flux into the flux of end product. By analyzing the characteristic and process of L-isoleucine fermentation based on 5L autocontrol fermentor,it was proved that metabolic pathways could be changed by the environmental factors such as dissolved oxygen. According to experimental result and metrology analysis, the metabolic flux is related to the dissolved oxygen, so dissolved oxygen can influence the yield of L-isoleucine by changing the the metabolic flux. In contrast to stable oxygen supply, grading oxygen supply is more superior. L-isoleucine of 25. 5g/L is accumulated by grading oxygen supply,and it is 15.77% higher than that of 20.26g/L by stable oxygen supply. On different stage of L-isoleucine fermentation, we can control oxygen supply to fulfill the different need of biomass growth and specific rate of L-isoleucine. The experimental conclusion is that oxygen supply on the basis of pathway analysis can be used in L-isoleucine fermentation.

关 键 词：L-异亮氨酸 途径分析 溶氧控制 黄色短杆菌 

分 类 号：TQ922.9[轻工技术与工程—发酵工程]