谷氨酸棒状杆菌发酵生产L-精氨酸的溶氧条件优化  

Optimization of Dissolved Oxygen Conditions for Corynebacterium glutamicum Producting L-arginine

作　　者：王震 WANG Zhen(School of Biological Science and Engineering, South China University of Technology, Guangzhou,Guangdong 511400)

机构地区：[1]华南理工大学生物科学与工程学院,广东广州511400

出　　处：《安徽农业科学》2019年第7期120-123,共4页Journal of Anhui Agricultural Sciences

基　　金：国家自然科学基金项目(31671840)

摘　　要：为了确定L-精氨酸发酵过程中最合适的溶氧浓度,通过控制5%、20%和35%这3种溶氧水平,探讨不同溶氧条件下的谷氨酸棒状杆菌ATCC14067-SG的L-精氨酸产量,并通过分析生长和关键代谢产物的方式,研究不同溶氧下精氨酸积累差异的原因。结果表明,在5%溶氧条件下,乳酸、丙氨酸、赖氨酸、鸟氨酸和谷氨酸的积累最高;35%溶氧条件下,乳酸、赖氨酸和鸟氨酸的积累有所改善,但丙氨酸和谷氨酸的积累仍然很高;在20%溶氧的发酵条件下,谷氨酸棒状杆菌的生长略好,且乳酸、丙氨酸、赖氨酸、鸟氨酸和谷氨酸的积累量显著降低。溶氧水平的不同,改变了谷氨酸棒状杆菌糖酵解和TCA循环的代谢流量。低溶氧条件下,TCA循环减弱,而过高的溶氧又会导致副产物的积累。在较为适中的20%溶氧下,谷氨酸棒状杆菌ATCC14067-SG的L-精氨酸产量最高,是35%溶氧水平的117.28%,5%溶氧水平的140.53%。In order to determine the most suitable dissolved oxygen concentration in the L-arginine fermentation process, the L-arginine production of Corynebacterium glutamicum ATCC14067-SG under different dissolved oxygen conditions was investigated by controlling the three dissolved oxygen levels of 5%, 20% and 35%. The reasons for the difference in arginine accumulation under different dissolved oxygen were studied by analyzing the growth and key metabolites. The results showed that under the condition of 5% dissolved oxygen, the accumulation of lactic acid, alanine, lysine, ornithine and glutamic acid were the highest. Under the condition of 35% dissolved oxygen, the accumulation of lactic acid, lysine and ornithine improved, but the accumulation of alanine and glutamic acid was still very high.Under the fermentation condition of 20% dissolved oxygen, the growth of C. glutamicum was slightly better, and the accumulation of lactic acid, alanine, lysine, ornithine and glutamic acid were significantly reduced. The difference in dissolved oxygen levels altered the metabolic flux in the glycolysis and TCA cycles of C. glutamicum . Under low dissolved oxygen condition, the TCA cycle was weakened, and too high dissolved oxygen led to accumulation of by-products. Under moderate 20% dissolved oxygen, C. glutamicum ATCC14067-SG had the highest L-arginine yield, which was 117.28% of the 35% dissolved oxygen level and 140.53% of the 5% dissolved oxygen level.

关 键 词：谷氨酸棒状杆菌 L-精氨酸 发酵工艺 溶氧 

分 类 号：TQ922[轻工技术与工程—发酵工程]