Bacillus subtilis degSU operon is regulated by the ClpXP-Spx regulated proteolysis system.
Bacillus subtilis degSU operon is regulated by the ClpXP-Spx regulated proteolysis system.
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枯草芽孢杆菌 degSU 操纵子受 ClpXP-Spx 调节的蛋白水解系统调节。
DOI：
10.1093/jb/mvu076
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发表时间：
2015
期刊：
影响因子：
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通讯作者：
Ogura M.
中科院分区：
文献类型：
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作者：
Shiwa Y;Yoshikawa H;Tanaka T;Ogura M.
DegS-DegU双组分调控系统在枯草芽孢杆菌中调节许多细胞事件。DegSU的基因构成由P1启动子指导的操纵子，并且下游degU通过磷酸化DegU激活的P3启动子自动调节。在革兰氏阳性菌中，Spx作为转录调节因子在抗氧化应激的保护系统中起主要作用。Spx是ATP依赖性ClpXP蛋白酶的底物。它调节二酰胺应激调节子以及许多功能未知的基因。我们已经发现，clpX和clpP的无效突变，其编码蛋白酶ClpXP的亚基，通过激活P1启动子提高DegU水平。我们分离了四种抑制lpP增强效应的抑制因子。对抑制基因的全基因组测序显示，其中两个基因有一个点突变，其余的有一个缺失。这些结果表明，degSU操纵子是Spx介导的正调控的新靶点。此外，我们发现P1启动子受葡萄糖诱导，并且这种诱导在px突变体中大大降低。这些结果表明，Spx介导的葡萄糖诱导在P1启动子。
The DegS-DegU two-component regulatory system regulates many cellular events inBacillus subtilis. Genes for DegSU constitutes an operon directed by the P1 promoter and downstreamdegUis autoregulated via the P3 promoter activated by phosphorylated DegU. In the Gram-positive bacteria, Spx plays a major role in the protection system against oxidative stresses as a transcriptional regulator. Spx is a substrate of the ATP-dependent ClpXP protease. It regulates diamide-stress regulon in addition to many genes with unknown functions. We have found that null mutations forclpXandclpP, which encode the subunits for the protease ClpXP, enhanced the DegU level through activation of the P1 promoter. We isolated four suppressors for theclpP-enhancing effect. Whole-genome sequencing of the suppressors revealed that two have a point mutation inspxand the rest have a deletion ofspx. TheclpP-enhancing effect ondegS-lacZexpression was abolished in thespxdisruptant.These results show that thedegSUoperon is a new target of Spx-mediated positive regulation. Furthermore, we found that the P1 promoter was induced by glucose and that this induction was greatly reduced in thespxmutant. These results suggested that Spx-mediated glucose induction at the P1 promoter.