柠檬酸钠对L–缬氨酸发酵及代谢流量分布的影响  

Effects of Sodium Citrate on Metabolic Flux Distributions of L-Valine Fermentation

作　　者：秦永锋[1] 徐庆阳[1] 谢希贤[1] 陈宁[1] 

机构地区：[1]工业微生物教育部重点实验室天津科技大学生物工程学院,天津300457

出　　处：《天津科技大学学报》2010年第2期9-12,33,共5页Journal of Tianjin University of Science & Technology

基　　金：天津市应用基础及前沿技术研究计划项目(08JCZDJC15400);天津市科技支撑计划重点项目(08ZCKFSH01900)

摘　　要：以黄色短杆菌XV0505为供试菌,研究柠檬酸钠对L–缬氨酸发酵的影响,同时应用MATLAB软件和代谢流量分析方法,定量研究柠檬酸钠对L–缬氨酸发酵中后期胞内代谢流量分布的影响.结果表明,添加2.0 g/L柠檬酸钠可提高L–缬氨酸产量,同时不影响菌体生长.添加柠檬酸钠后,L–缬氨酸生物合成的代谢流从41.42增长至45.87,较未添加前提高了10.74%.合成副产物L–丙氨酸和HAc的代谢流明显减少,分别降低了21.10%和32.47%.因此,添加柠檬酸钠能够扰动L–缬氨酸生物合成途径关键节点代谢流量分布,有利于减少副产物的生成,提高L–缬氨酸生物合成途径的代谢流量.In order to quantitatively analyze the effects of sodium citrate on the metabolic flux distributions in Brevibacterium flavum XV0505 during the middle and late period, the metabolic flux analysis and MATLAB software were conducted, based on researches in effects of sodium citrate on fermentation. It was revealed that a increase of the formation of L-valine can be observed with the fermentation medium supplemented sodium citrate （2.0 g/L）. The metabolic flux channeled to the L-valine synthesis pathway increased by 10.74%（from 41.42 to 45.87）. Moreover, the formation of byproducts, such as L-Ala and HAc, deceases 21.10% and 32.47% respectively. All of these show that the addition of sodium citrate can change the metabolic flux distributions of the key nodes, lead to the decrease of byproducts formation and strengthen the L-valine biosynthesis.

关 键 词：L-缬氨酸 黄色短杆菌 代谢流分析 柠檬酸钠 

分 类 号：Q93[生物学—微生物学]