...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of bacteriology >Dual Repression by Fe2+-Fur and Mn2+-MntR of the mntH Gene, Encoding an NRAMP-Like Mn2+ Transporter in Escherichia coli
【24h】

Dual Repression by Fe2+-Fur and Mn2+-MntR of the mntH Gene, Encoding an NRAMP-Like Mn2+ Transporter in Escherichia coli

机译：Fe2 + -Fur和Mn2 + -MntR对mntH基因的双重抑制，在大肠杆菌中编码类似于NRAMP的Mn2 +转运蛋白

获取原文
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The uptake of Mn2+, a cofactor for several enzymes inEscherichia coli, is mediated by MntH, a proton-dependent metal transporter, which also recognizes Fe2+ with lower affinity. MntH belongs to the NRAMP family of eukaryotic Fe2+ and Mn2+ transporters. In E. coli strains with chromosomal mntH-lacZ fusions,mntH was partially repressed by both Mn2+ and Fe2+. Inactivation of fur resulted in the loss of Fe2+-dependent repression of mntHtranscription, demonstrating that Fe2+ repression depends on the global iron regulator Fur. However, these furmutants still showed Mn2+-dependent repression ofmntH. The Mn2+-responsive transcriptional regulator of mntH was identified as the gene product ofo155 (renamed MntR). mntR mutants were impaired in Mn2+ but not Fe2+ repression ofmntH transcription. Binding of purified MntR to themntH operator was manganese dependent. The binding region was localized by DNase I footprinting analysis and covers a nearly perfect palindrome. The Fur binding site, localized within 22 nucleotides of the mntH operator by in vivo operator titration assays, resembles the Fur-box consensus sequence.
机译：Mn 2 + 是大肠杆菌中几种酶的辅助因子，其吸收由质子依赖性金属转运体MntH介导，MntH也识别Fe 2 + 的亲和力较低。 MntH属于真核Fe 2 + 和Mn 2 + 转运蛋白的NRAMP家族。在 E中。带有 mntH-lacZ 染色体融合的大肠杆菌， mntH 均被Mn 2 + 和Fe 2+部分抑制。 fur 的失活导致了 mntH 转录的Fe 2 + 依赖性抑制的丧失，表明Fe 2 + 镇压取决于全球铁调节剂Fur。然而，这些 fur 突变体仍然显示出 mntH 的Mn 2 + 依赖性依赖。鉴定出 mntH 的Mn 2 + 响应转录调节因子为 o155 的基因产物（重命名为MntR）。 mntR 突变体在Mn 2 + 的抑制中受损，但对Fe 2 + 抑制 mntH 的转录没有影响。纯化的MntR与 mntH 操纵子的结合依赖于锰。结合区通过DNase I足迹分析进行定位，并覆盖了几乎完美的回文。通过体内操作员滴定分析，Fur结合位点位于 mntH 操纵子的22个核苷酸内，与Fur-box共有序列相似。

著录项

相似文献

  • 外文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号