谷氨酸棒杆菌生物合成L-鸟氨酸的代谢流分析

Metabolic flux analysis of L-ornithine biosynthesis by Corynebacterium glutamicum

应用代谢流平衡模型,通过物料衡算和Matlab线性规划的方法得到谷氨酸棒杆菌1009生物合成L-鸟氨酸的代谢流分布与理想代谢流分布.结果表明:在分批培养条件下,生物合成L-鸟氨酸的过程中,有58.6%的C架进入糖酵解途径,41.4%的C架进入戊糖磷酸途径,L-鸟氨酸的产量达到理论最大产率的65.4%;与理论值相比,应降低三羧酸循环的代谢流,同时减少副产物氨基酸和有机酸的生成.

The metabolic flux balance model of L-ornithine synthesis by Corynebacterium glutamicum 1009 was constructed. Using the model, the metabolic flux distribution was determined and the optimal flux distribution was calculated by Matlab method. Results showed that 58. 6% metabolic flux entered the Embden-MeyerhofParnas pathway and 41.4% entered the hexose monophophate pathway. Compared with the optimal flux distributions, the production of L-ornithine achieved 65.4% of the theory maximum yield. The production of L-ornithine could be improved from the genetic manipulation and the fermentation control through reducing byproduct of amino acid and organic acid and decreasing the flux of trichloroacetic acid cycle.