POSITIVE CONTROL OF A GLOBAL ANTIOXIDANT DEFENSE REGULON ACTIVATED BY SUPEROXIDE-GENERATING AGENTS IN ESCHERICHIA-COLI
POSITIVE CONTROL OF A GLOBAL ANTIOXIDANT DEFENSE REGULON ACTIVATED BY SUPEROXIDE-GENERATING AGENTS IN ESCHERICHIA-COLI
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DOI：
10.1073/pnas.87.16.6181
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发表时间：
1990-08-01
影响因子：
11.1
通讯作者：
DEMPLE, B
中科院分区：
文献类型：
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作者：
GREENBERG, JT;MONACH, P;DEMPLE, B
大肠杆菌通过诱导.apprxeq对超氧化物产生剂作出反应。40的蛋白质。我们已经确定了一个基因位点，soxR（超氧化物反应），在超氧化物胁迫下积极调节这些蛋白质中的9种。在soxR控制下的诱导是在转录水平上，如lac与五个百草枯诱导启动子的融合所示。soxR调控的成员包括至少三种具有明显抗氧化作用的蛋白质：含锰超氧化物歧化酶（破坏超氧化物自由基），核内切酶IV（修复自由基引起的DNA损伤）和葡萄糖-6-磷酸脱氢酶（产生NADPH）。sor调控的诱导也导致主要外膜蛋白OmpF水平的降低和小亚基核糖体蛋白S6的改变。后一种变化使细菌对多种抗生素产生耐药性。因此，一般来说，soxR调控可以作为一种诱导防御外来物的机制。
Escherichia coli responds to superoxide-generating agents by inducing .apprxeq. 40 proteins. We have identified a genetic locus, soxR (superoxide response), that positively regulates 9 of these proteins during superoxide stress. Induction under soxR control is at the transcriptional level, as shown with lac fusions to five paraquat-inducible promoters. Members of the soxR regulon include at least three proteins with demonstrable antioxidant roles: Mn-containing superoxide dismutase (which destroys superoxide radicals), endonuclese IV (which repairs radical-induced damages in DNA), and glucose-6-phosphate dehydrogenase (which produces NADPH). Induction of the soxR regulon also leads to diminished levels of the major outer membrane protein OmpF and alteration of the small-subunit ribosomal protein S6. These latter changes confer resistance to a variety of antibiotics. The soxR regulon may thus operate as an inducible defense against xenobiotics in general.