Spx mediates oxidative stress regulation of the methionine sulfoxide reductases operon in Bacillus subtilis.
Spx mediates oxidative stress regulation of the methionine sulfoxide reductases operon in Bacillus subtilis.
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SPX介导了枯草芽孢杆菌中甲硫氨酸还原酶操纵子的氧化应激调节。
DOI：
10.1186/1471-2180-8-128
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发表时间：
2008-07-28
期刊：
影响因子：
4.2
通讯作者：
Danchin, Antoine
中科院分区：
文献类型：
--
作者：
You, CongHui;Sekowska, Agnieszka;Francetic, Olivera;Martin-Verstraete, Isabelle;Wang, YiPing;Danchin, Antoine
所有有氧生长的活细胞都暴露在活性氧（ROS）的氧化损伤中。活性氧对蛋白质的主要损害是由蛋氨酸残基的共价修饰引起的，产生蛋氨酸亚砜（Met-SO）。蛋氨酸亚砜还原酶是一种在氧化损伤后能够使蛋氨酸再生并恢复蛋白质功能的酶。我们在枯草芽孢杆菌中鉴定了蛋氨酸亚砜还原酶基因msrA和msrB，形成了一个由单个sigma a依赖性启动子转录的操纵子。msrAB操纵子可被百草枯（PQ）引起的氧化应激特异性诱导，而非H2O2。Spx是枯草芽孢杆菌中的一种全球性氧化应激调节因子，主要负责pq特异性诱导msrAB表达。为了支持这一发现，spx缺失突变体对PQ非常敏感，并且在spx积累的clpX突变体中发现msrA表达增加。然而，在蛋白质不积累的条件下（PQ处理），Spx效应也很明显，这表明在Spx蛋白水平上存在特定的分子效应。事实上，Spx的CXXC基序在pq特异性诱导msrAB表达中起着至关重要的作用。PQ引起Spx的修饰，需要Spx的CXXC基序的至少一个半胱氨酸。PQ修饰后的Spx在体内呈动态变化。报道了枯草芽孢杆菌中Spx介导的msrAB操纵子pq特异性调控途径。我们的研究结果表明，PQ诱导msrAB的表达部分是通过修饰Spx的CXXC基序来氧化Spx。
All aerobically grown living cells are exposed to oxidative damage by reactive oxygen species (ROS). A major damage by ROS to proteins is caused by covalent modifications of methionine residues giving methionine sulfoxide (Met-SO). Methionine sulfoxide reductases are enzymes able to regenerate methionine and restore protein function after oxidative damage. We characterized the methionine sulfoxide reductase genes msrA and msrB in Bacillus subtilis, forming an operon transcribed from a single sigma A-dependent promoter. The msrAB operon was specifically induced by oxidative stress caused by paraquat (PQ) but not by H2O2. Spx, a global oxidative stress regulator in B. subtilis, is primarily responsible for this PQ-specific induction of msrAB expression. In support of this finding, an spx deletion mutant is extremely sensitive to PQ, and increased expression of msrA was identified in a clpX mutant in which Spx accumulated. However, the Spx effect was also visible under conditions where the protein did not accumulate (PQ treatment), suggesting a specific molecular effect at the level of the Spx protein. Indeed, the CXXC motif of Spx was found essential for its function in the PQ-specific induction of msrAB expression. PQ caused a modification of Spx requiring at least one of the cysteines of the CXXC motif of Spx. The PQ modified form of Spx showed a dynamic change in vivo. The Spx mediated PQ-specific regulation pathway of the msrAB operon in B. subtilis is reported. Our results suggest that PQ induced the expression of msrAB partially through an oxidation on Spx via modification of its CXXC motif.
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影响因子：
2.9
作者：
Antelmann, H;Bernhardt, J;Hecker, M
通讯作者：
Hecker, M
DOI：
10.1196/annals.1354.006
发表时间：
2006-01-01
期刊：
UNDERSTANDING AND MODULATING AGING
影响因子：
--
作者：
Cabreiro, Filipe;Picot, Cedric R.;Petropoulos, Isabelle
通讯作者：
Petropoulos, Isabelle
影响因子：
3.2
作者：
CALOGERO, S;GARDAN, R;DEBARBOUILLE, M
通讯作者：
DEBARBOUILLE, M
影响因子：
3.6
作者：
Nair, S;Derré, I;Berche, P
通讯作者：
Berche, P
影响因子：
3.2
作者：
Alamuri, Praveen;Maier, Robert J.
通讯作者：
Maier, Robert J.