细胞内氧化还原水平对大肠杆菌厌氧代谢产物的影响
he effect of in vivo redox level on Escherichia coli fermentation products distribution
对以葡萄糖，葡萄糖酸和山梨糖醇为发酵碳源时厌氧状态下的大肠杆菌的生长和代谢产物的分布进行了测定，结合NADH、NAD+的测量表明，NADH/NAD+的比例确实可以改变大肠杆菌发酵产物的分布。高还原性的发酵碳源有利于还原性产物乙醇的发酵，而琥珀酸的得率有微量的上升。通过细胞内表达假丝酵母甲酸脱氢酶提高NADH/NAD+的比例后，野生大肠杆菌对葡萄糖的消耗加快，消耗了发酵过程中产生的甲酸，因此甲酸在发酵结束后含量非常低，而乙醇的得率提高，琥珀酸的得率变化很小。在adhE基因敲除菌TUQ5中表达甲酸脱氢酶从而提高NADH/NAD+的比例后，TUQ5菌株的生长受到了比较大的影响，TUQ5发酵只能产生极少量的乙醇，除乳酸和乙醇得率有不同程度的上升以外，其它发酵副产物均下降。
he anaerobic fermentation products distributions of E.coli were analyzed when different carbon sources, glucose, gluconate, sorbitol were used as the fermentation carbon. With the combinations of in vivo NADH, NAD+ measurement, the results showed that NADH/NAD+ can actually change the anaerobic fermentation products distributions. The reduced carbon sources can produce more ethanol and the succinate is also increased slightly. The formate dehydrogenase (FDH) of Candida boidini expression plasmid pQZ8 was constructed to improve the NADH/NAD+ ratio. After expression of FDH, the wild type E. coli consumed glucose more quickly and the ethanol yield was increased sharply, however, the yield of succinate was almost not changed. The adhE deletion strain TUQ5 was constructed also. After the expression of FDH in TUQ5, the growth is hampered and all the products were decreased except lactate and ethanol.
赵学明、王庆昭、李宁
生物化学微生物学分子生物学
NAD+/NADH大肠杆菌甲酸脱氢酶厌氧发酵代谢产物分布
NAD+/NADHEscherchia .coliformate dehydrogenaseanaerobic fermentationproducts distribution
赵学明,王庆昭,李宁.细胞内氧化还原水平对大肠杆菌厌氧代谢产物的影响[EB/OL].(2010-05-03)[2025-08-02].http://www.paper.edu.cn/releasepaper/content/201005-2.点此复制
评论