Regulation of the soxRS Oxidative Stress Regulon
Regulation of the soxRS Oxidative Stress Regulon
复制标题
soxRS 氧化应激调节子的调节
DOI：
--
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发表时间：
1997
影响因子：
4.8
通讯作者：
B. Weiss
中科院分区：
文献类型：
--
作者：
P. Gaudu;Namdoo Moon;B. Weiss
SoxR蛋白是大肠杆菌soxRS（superoxideresponse）调节子的转录激活因子，含有可自氧化的[2Fe-2S]中心，被认为是氧化还原传感器。先前的体外转录实验表明，只有氧化形式是有活性的。通过完整细胞悬浮液的EPR光谱检测到过量生产菌株中的SoxR减少。通过裂解细胞并在EPR测量之前用还原剂连二亚硫酸钠处理它们来确定氧化的Fe-S中心。在未诱导的细胞中，90%的SoxR是还原形式。用氧化还原循环剂吩嗪硫酸甲酯或白花丹精处理伴随着Fe-S中心的可逆氧化。组成性激活的突变体SoxR衍生物以氧化状态组成性存在。结果表明存在细胞途径对抗SoxR的自氧化，并证实了调节子的诱导是由SoxR的氧化还原平衡的转变介导的假设，而不是由其Fe-S簇的组装。
SoxR protein, a transcriptional activator of the soxRS (superoxide response) regulon of Escherichia coli, contains autooxidizable [2Fe-2S] centers that are presumed to serve as redox sensors. In vitro transcription experiments previously demonstrated that only the oxidized form is active. Reduced SoxR was detected in overproducing strains by EPR spectroscopy of suspensions of intact cells. Oxidized Fe-S centers were determined by lysing the cells and treating them with the reducing agent sodium dithionite prior to EPR measurements. In uninduced cells, 90% of the SoxR was in the reduced form. Treatment with the redox cycling agents phenazine methosulfate or plumbagin was accompanied by reversible oxidation of the Fe-S centers. Mutant SoxR derivatives that were constitutively activated existed constitutively in an oxidized state. The results indicate the presence of a cellular pathway for countering the autooxidation of SoxR and confirm the hypothesis that induction of the regulon is mediated by a shift in the redox equilibrium of SoxR rather than by assembly of its Fe-S clusters.
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影响氧化还原敏感 SoxR 转录激活因子 C 末端的一组组成型突变。
影响因子：
14.9
作者：
Nunoshiba,T;Demple,B
通讯作者：
Demple,B
DOI：
10.1073/pnas.84.10.3189
发表时间：
1987-05-01
影响因子：
11.1
作者：
CHAN, E;WEISS, B
通讯作者：
WEISS, B
DOI：
10.1073/pnas.90.21.9993
发表时间：
1993-11-01
影响因子：
11.1
作者：
NUNOSHIBA, T;DEROJASWALKER, T;DEMPLE, B
通讯作者：
DEMPLE, B
铁硫簇在大肠杆菌核酸内切酶 III 中的作用。
DOI：
--
发表时间：
1992
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Fu,W;O'Handley,S;Cunningham,RP;Johnson,MK
通讯作者：
Johnson,MK