Identification of IbeR as a stationary-phase regulator in meningitic Escherichia coli K1 that carries a loss-of-function mutation in rpoS.
Identification of IbeR as a stationary-phase regulator in meningitic Escherichia coli K1 that carries a loss-of-function mutation in rpoS.
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DOI：
10.1155/2009/520283
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发表时间：
2009
影响因子：
--
通讯作者：
Huang SH
中科院分区：
文献类型：
--
作者：
Chi F;Wang Y;Gallaher TK;Wu CH;Jong A;Huang SH
IbeR是存在于脑膜炎大肠杆菌菌株E44中的一种调节剂，该菌株在静止期（SP）调节基因rpoS中携带功能丧失突变。为了确定IbeR是否在E44中是SP的调节因子，我们使用二维凝胶电泳和LC-MS对无创IbeR缺失突变体BR2及其亲本菌株E44在SP中的蛋白质组进行了比较。与E44相比，在BR2中鉴定出4个上调蛋白（TufB、GapA、OmpA、AhpC）和3个下调蛋白（LpdA、TnaA、OpmC）。这些蛋白都参与能量代谢或抗逆性，与SP调控有关。其中一种下调蛋白，色氨酸酶（TnaA），在其他大肠杆菌菌株中受RpoS调节，通过产生信号分子吲哚与SP调节有关。我们的研究表明，TnaA是E44入侵所必需的，吲哚能够恢复TnaA突变体的非侵入性表型。在BR2中吲哚的产生显著减少，表明ibeR是通过tnaA产生吲哚所必需的。不同胁迫条件下的生存研究表明，IbeR有助于SP中细菌的抗性。综上所述，IbeR是一种参与SP调控的新型调节剂。
IbeR is a regulator present in meningitic Escherichia coli strain E44 that carries a loss-of-function mutation in the stationary-phase (SP) regulatory gene rpoS. In order to determine whether IbeR is an SP regulator in E44, two-dimensional gel electrophoresis and LC-MS were used to compare the proteomes of a noninvasive ibeR deletion mutant BR2 and its parent strain E44 in the SP. Four up-regulated (TufB, GapA, OmpA, AhpC) and three down-regulated (LpdA, TnaA, OpmC) proteins in BR2 were identified when compared to E44. All these proteins contribute to energy metabolism or stress resistance, which is related to SP regulation. One of the down-regulated proteins, tryptophanase (TnaA), which is regulated by RpoS in other E. coli strains, is associated with SP regulation via production of a signal molecule indole. Our studies demonstrated that TnaA was required for E44 invasion, and that indole was able to restore the noninvasive phenotype of the tnaA mutant. The production of indole was significantly reduced in BR2, indicating that ibeR is required for the indole production via tnaA. Survival studies under different stress conditions indicated that IbeR contributed to bacteria stress resistance in the SP. Taken together, IbeR is a novel regulator contributing to the SP regulation.
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影响因子：
4
作者：
Deghmane, Ala-Eddine;Soulhine, Hafid;Hmama, Zakaria
通讯作者：
Hmama, Zakaria
影响因子：
4.2
作者：
Coldewey SM;Hartmann M;Schmidt DS;Engelking U;Ukena SN;Gunzer F
通讯作者：
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影响因子：
5.6
作者：
Johansen, Jesper;Rasmussen, Anders Aamann;Valentin-Hansen, Poul
通讯作者：
Valentin-Hansen, Poul
影响因子：
3.1
作者：
HUANG, SH;WASS, C;KIM, KS
通讯作者：
KIM, KS
影响因子：
3.1
作者：
Hoffman, JA;Badger, JL;Kim, KS
通讯作者：
Kim, KS