Cofactor engineering through heterologous expression of an NADH oxidase and its impact on metabolic flux redistribution in Klebsiella pneumoniae.
Cofactor engineering through heterologous expression of an NADH oxidase and its impact on metabolic flux redistribution in Klebsiella pneumoniae.
复制标题
通过 NADH 氧化酶异源表达进行辅因子工程及其对肺炎克雷伯菌代谢通量重新分布的影响
DOI：
10.1186/1754-6834-6-7
复制
发表时间：
2013-01-25
影响因子：
6.3
通讯作者：
Huang H
中科院分区：
文献类型：
--
作者：
Ji XJ;Xia ZF;Fu NH;Nie ZK;Shen MQ;Tian QQ;Huang H
背景
乙偶姻是一种重要的生物基平台化学品。然而，它通常作为2，3-丁二醇发酵的少量副产物存在于细菌中。
结果
本研究报道了将外源NAD+再生系统引入2，3-丁二醇产生菌肺炎克雷伯氏菌（Klebsiellapneumoniae）中，以提高乙偶姻的积累。分批发酵表明，在K. pneumoniae引起细胞内NADH浓度（1.4倍）和NADH/NAD+比率（2.0倍）的大幅降低。代谢通量分析表明，乙偶姻和乙酸的通量增加，而乳酸和乙醇的产量下降，与2，3-丁二醇的结晶几乎不变。通过补料分批培养，获得了克雷伯氏菌属的最高乙偶姻生产水平（25.9g/L）。
结论
本研究表明，降低K.肺炎。这表明，辅因子工程方法，这是通过操纵细胞内辅因子的水平，以重新定向细胞代谢，可以用来实现高效率的生产NAD+依赖性微生物代谢产物。
Background
Acetoin is an important bio-based platform chemical. However, it is usually existed as a minor byproduct of 2,3-butanediol fermentation in bacteria.
Results
The present study reports introducing an exogenous NAD+ regeneration sysytem into a 2,3-butanediol producing strain Klebsiella pneumoniae to increse the accumulation of acetoin. Batch fermentation suggested that heterologous expression of the NADH oxidase in K. pneumoniae resulted in large decreases in the intracellular NADH concentration (1.4 fold) and NADH/NAD+ ratio (2.0 fold). Metabolic flux analysis revealed that fluxes to acetoin and acetic acid were enhanced, whereas, production of lactic acid and ethanol were decreased, with the accumualation of 2,3-butanediol nearly unaltered. By fed-batch culture of the recombinant, the highest reported acetoin production level (25.9 g/L) by Klebsiella species was obtained.
Conclusions
The present study indicates that microbial production of acetoin could be improved by decreasing the intracellular NADH/NAD+ ratio in K. pneumoniae. It demonstrated that the cofactor engineering method, which is by manipulating the level of intracellular cofactors to redirect cellular metabolism, could be employed to achieve a high efficiency of producing the NAD+-dependent microbial metabolite.
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消除产酸克雷伯菌中碳分解代谢物的抑制，以从葡萄糖-木糖混合物中高效生产 2,3-丁二醇
影响因子：
5
作者：
Ji, Xiao-Jun;Nie, Zhi-Kui;Ouyang, Ping-Kai
通讯作者：
Ouyang, Ping-Kai
影响因子：
8.4
作者：
Hou, Jin;Lages, Nuno F.;Vemuri, Goutham N.
通讯作者：
Vemuri, Goutham N.
DOI：
10.1007/s10295-002-0006-0
发表时间：
2003-01-01
影响因子：
3.4
作者：
Berríos-Rivera, SJ;San, KY;Bennett, GN
通讯作者：
Bennett, GN
影响因子：
2.9
作者：
LILIUS, EM;MULTANEN, VM;TOIVONEN, V
通讯作者：
TOIVONEN, V
影响因子：
2.9
作者：
BERNOFSKY, C;SWAN, M
通讯作者：
SWAN, M