The soluble transhydrogenase UdhA affecting the glutamate-dependent acid resistance system of Escherichia coli under acetate stress.
The soluble transhydrogenase UdhA affecting the glutamate-dependent acid resistance system of Escherichia coli under acetate stress.
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可溶性转氢酶UdhA对乙酸胁迫下大肠杆菌谷氨酸依赖性耐酸系统的影响
DOI：
10.1242/bio.031856
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发表时间：
2018-09-10
期刊：
影响因子：
2.4
通讯作者：
Zhu G
中科院分区：
文献类型：
--
作者：
Zhao H;Zhou F;Xing Q;Cao Z;Liu J;Zhu G
可溶性转氢酶（UdhA）是大肠杆菌中维持NAD（H）库和NADP（H）库平衡的两种转氢酶之一。虽然UdhA已被广泛应用于代谢工程和生物催化的辅因子再生，其在抗酸性的作用还没有报道。在这里，我们使用DNA微阵列来探索UdhA对转录水平的影响。我们证明，在乙酸盐上生长期间，参与呼吸链和Gad酸抗性系统的基因的表达在udhA敲除菌株中被抑制。udhA的缺失显著抑制了参与Gad酸抗性的六个基因（gadA、gadB、gadC、gadE、hdeA和hdeB）的表达，并导致细菌在4.9的低pH下存活率低。此外，UdhA是大肠杆菌适应性生长所必需的NADH合成酶。而udhA敲除菌株中的NADH浓度相当低，补充NADH显著增加了udhA敲除菌株的耐酸性基因表达和存活。这些结果表明UdhA是大肠杆菌NADH的重要来源。大肠杆菌在乙酸盐上的生长，并在乙酸盐胁迫下影响Gad抗酸系统。总结：UdhA的功能有助于我们了解UdhA在乙酸盐环境中影响大肠杆菌NADH产生和Gad耐酸性系统的生理作用。
ABSTRACT The soluble transhydrogenase (UdhA) is one of two transhydrogenases that play a role in maintaining the balance between NAD(H) pools and NADP(H) pools in Escherichia coli. Although UdhA has been extensively used in metabolic engineering and biocatalysis for cofactor regeneration, its role in acid resistance has not been reported. Here we used DNA microarray to explore the impact of UdhA on transcript levels. We demonstrated that during growth on acetate, the expression of genes involved in the respiratory chain and Gad acid resistance system was inhibited in the udhA-knockout strain. The deletion of udhA significantly repressed the expression of six genes (gadA, gadB, gadC, gadE, hdeA and hdeB) which are involved in Gad acid resistance and resulted in low survival of the bacterium at a low pH of 4.9. Moreover, UdhA was essential for NADH production which is important for the adaptive growth of E. coli on acetate, while NADH concentration in the udhA-knockout strain was quite low and supplemental NADH significantly increased the expression of acid resistance genes and survival of the udhA-knockout strain. These results demonstrated that UdhA is an important source of NADH of E. coli growth on acetate and affects Gad acid resistance system under acetate stress. Summary: UdhA function stated in this study helps us to understand the physiological roles of UdhA affecting NADH production and Gad acid resistance system in E.coli in acetate environment.
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影响因子：
3.2
作者：
Arnold, CN;McElhanon, J;Siegele, DA
通讯作者：
Siegele, DA
影响因子：
3.2
作者：
Castanie-Cornet, MP;Penfound, TA;Foster, JW
通讯作者：
Foster, JW
影响因子：
3.2
作者：
Masuda, N;Church, GM
通讯作者：
Church, GM
影响因子：
3.2
作者：
Kern, Renee;Malki, Abderrahim;Richarme, Gilbert
通讯作者：
Richarme, Gilbert
DOI：
10.1073/pnas.120163297
发表时间：
2000-06-06
影响因子：
11.1
作者：
Datsenko, KA;Wanner, BL
通讯作者：
Wanner, BL