Identification and molecular analysis of oxyR-regulated promoters important for the bacterial adaptation to oxidative stress.
Identification and molecular analysis of oxyR-regulated promoters important for the bacterial adaptation to oxidative stress.
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DOI：
10.1016/0022-2836(89)90104-6
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发表时间：
1989-12
影响因子：
5.6
通讯作者：
L. Tartaglia;G. Storz;B. Ames
中科院分区：
文献类型：
--
作者：
L. Tartaglia;G. Storz;B. Ames
TheoxyR 编码的调节蛋白 OxyR 可诱导鼠伤寒沙门氏菌和大肠杆菌中过氧化氢诱导蛋白家族的合成。为了进一步确定whichoxyR调节这些蛋白质的产生的机制，我们鉴定、定位和表征了theS上游的oxyR调节的启动子。鼠伤寒杆菌 ahpgenes（编码烷基氢过氧化物还原酶）和大肠杆菌。大肠杆菌 katG 基因（编码过氧化氢酶）。在体外构建了一组ahpC启动子缺失，并且对这些缺失的分析揭示了参与oxyR介导的ahpC基因产物诱导的序列的位置。 ahpC 启动子区域的 DNase I 保护研究揭示了 anoxyR 依赖性足迹，该足迹与重要的 foroxyRcontrol 序列重叠。含有thekatG启动子和thelacZ基因之间转录融合的大肠杆菌显示出响应于过氧化氢处理的β-半乳糖苷酶合成的强烈增加。发现这种刺激依赖于beoxyR。 katG 启动子区域的 DNase I 保护研究揭示了与 ahpC 启动子中观察到的相对于基础启动子元件相同位置的 anoxyR 依赖性足迹。尽管显示ahpCandkatG启动子结合相同的因子，但在两者之间或两者与E上游的第三氧基R依赖性结合位点之间没有发现强序列相似性。大肠杆菌氧基因本身。
TheoxyR-encoded regulatory protein, OxyR, acts to induce the synthesis of a family of hydrogen peroxide-inducible proteins inSalmonella typhimuriumandEscherichia coli. To further define the mechanism by whichoxyRregulates the production of these proteins, we identified, mapped, and characterizedoxyR-regulated promoters upstream from theS. typhimurium ahpgenes (encoding an alkyl hydroperoxide reductase) and theE. coli katGgene (encoding catalase). A set ofahpCpromoter deletions was constructedin vitroand analysis of these deletions revealed the location of sequences that are involved inoxyR-mediated induction of theahpCgene product. DNase I protection studies of theahpCpromoter region revealed anoxyR-dependent footprint that overlapped the sequences found to be important foroxyRcontrol.E. colistrains containing transcriptional fusions between thekatGpromoter and thelacZgene showed strongly increased synthesis of β-galactosidase in response to hydrogen peroxide treatment. This stimulation was found to beoxyR-dependent. DNase I protection studies of thekatGpromoter region revealed anoxyR-dependent footprint in the same location relative to the basal promoter elements as was observed with theahpCpromoter. Although both theahpCandkatGpromoters were shown to bind the same factor, no strong sequence similarities were found between the two, or between the two and a thirdoxyR-dependent binding site upstream from theE. coli oxyRgene itself.