Differential activities of the SoxR protein of Escherichia coli:: SoxS is not required for gene activation under iron deprivation
Differential activities of the SoxR protein of Escherichia coli:: SoxS is not required for gene activation under iron deprivation
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DOI：
10.1111/j.1574-6968.2001.tb10768.x
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发表时间：
2001-07-24
影响因子：
2.1
通讯作者：
Amábile-Cuevas, CF
中科院分区：
文献类型：
--
作者：
Fuentes, AM;Díaz-Mejía, JJ;Amábile-Cuevas, CF
当大肠杆菌细胞处于超氧胁迫下时，SoxR和SoxS蛋白依次作用，控制一系列修复和防御基因的表达。其中一个编码富马酸酶C的基因fumC被报道也被铁剥夺以SOxRS依赖的方式激活。然而，同样的条件未能诱导Soxs‘：：LacZ融合基因的表达。在缺铁条件下，仅SOxR能激活ACNA(乌头酸酶A)的表达，而苏打(Mn-超氧化物歧化酶)不能激活ACNA(乌头酸酶A)的表达。在凝胶位移实验中，SoxR完全抑制了含有fumC启动子区域的DNA片段的迁移。SoxR可能与fumC启动子中与SoxS不同的区域结合，或者可能是SOXS以外的未知中间体起作用。SoxR的监管角色可能比之前认为的更复杂。(C)2001年，埃尔塞维尔科学公司代表欧洲微生物学会联合会出版。
When Escherichia coli cells are under superoxide stress, proteins SoxR and SoxS, acting sequentially, control the expression of a set of repair and defense genes. One of these genes, fumC, encoding fumarase C, was reported to be also activated by iron deprivation in a soxRS-dependent manner. However, the same condition failed to induce the expression of a soxS':: lacZ fusion. The expression of acnA (aconitase A) is also activated by SoxR alone when under iron deprivation, but not of sodA (Mn-superoxide-dismutase). SoxR completely inhibited the migration of a DNA fragment containing the promoter region of fumC, in gel-shift experiments. SoxR might bind to a different region than SoxS within the fumC promoter, or an unknown intermediate other than SoxS might be acting. It is possible that the regulatory role of SoxR is more complex than previously considered. (C) 2001 Published by Elsevier Science B.V. on behalf of the Federation of European Microbiological Societies.