空气SR,一个含有 [2Fe-2S] 集群的两组件系统,在黄金葡萄球菌中调解全球氧气传感和氧化还原信号
Fei Sun1, Quanjiang Ji, Marcus B Jones
1Department of Chemistry and Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637, USA.
Journal of the American Chemical Society
|November 30, 2011
概括
金黄色葡萄球菌使用AirSR系统通过氧化还原活性铁硫来感知氧化信号. 这个系统调节数百个基因,并在氧气有限的条件下影响抗生素耐药性.
科学领域:
- 微生物学 微生物学
- 细菌生理学 细菌生理学
- 电解氧信号传输 电解氧信号传输
背景情况:
- 氧气传感和氧化还原信号对于细菌生理学和宿主-病原体相互作用至关重要.
- 两组系统是细菌中的关键调节器,通常会对环境线索做出反应.
研究的目的:
- 阐明 Staphylococcus aureus AirSR 两部分系统对氧化信号的反应的功能和机制.
- 研究铁硫集群在AirS激酶活性中的作用及其对基因调节和抗生素耐药性的影响.
主要方法:
- 位点定向的突变发生,以研究 [2Fe-2S] 集群的作用.
- 在体外复制 [2Fe-2S] 集群,使用氨酸脱硫酶同类物.
- 酸化试验以确定激酶活性.
- 转录组分析 (RNA-seq) 来识别受调节的基因.
- 抗微生物耐药性测试.
主要成果:
- 在AirS中的 [2Fe-2S] 集群对其酶活性至关重要,氧化 [2Fe-2S] 2+) 形式完全活跃.
- 集群的过度氧化或减少使AirS.失活.
- 在无氧条件下,airR的突变会影响大约355个基因的表达.
- 在无氧条件下,airR突变体对H2O2,万科米辛,诺弗洛克萨辛和西普罗夫洛克萨辛的耐药性增加.
结论:
- 金黄色葡萄球菌AirSR是一种依赖于氧化还原的全球调节系统.
- 该系统利用AirS中的氧化还原活性铁硫集群来感知氧化信号.
- 在基因调节中,AirSR扮演着重要的角色,在氧气有限的条件下,它会对各种药物产生耐药性.
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