• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Molecular Biology >Conformational changes of the ferric uptake regulation protein upon metal activation and DNA binding; first evidence of structural homologies with the diphtheria toxin repressor
【24h】

Conformational changes of the ferric uptake regulation protein upon metal activation and DNA binding; first evidence of structural homologies with the diphtheria toxin repressor

机译：金属激活和DNA结合后铁摄取调节蛋白的构象变化;白喉毒素阻遏物结构同源的第一个证据

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Fur (ferric uptake regulation protein) is a bacterial global regulator that uses iron as a cofactor to bind to specific DNA sequences. It has been suggested that metal binding induces a conformational change in the protein, which is subsequently able to recognize DNA. This mechanism of activation has been investigated here using selective chemical modification monitored by mass spectrometry. The reactivity of each lysine residue of the Fur protein was studied, first in the apo form of the protein, then after metal activation and finally after DNA binding. Of particular interest is Lys76, which was shown to be highly protected from modification in the presence of target DNA. Hydrogen-deuterium exchange experiments were performed to map with higher resolution the conformational changes induced by metal binding. On the basis of these results, together with a secondary structure prediction, the presence in Fur of a non-classical helix-turn-helix motif is proposed. Experimental results show that activation upon metal binding induces conformational modification of this specific motif. The recognition helix, interacting directly with the major groove of the DNA, would include the domain [Y55-F61]. This helix would be followed by a small "wing" formed between two beta strands, containing Lys76, which might interact directly with DNA. These results suggest that Fur and DtxR (diphtheria toxin repressor), another bacterial repressor, share not only the function of being iron concentration regulators, and the structure of their DNA-binding domain. (C) 2001 Academic Press. [References: 33]
机译：毛发（铁摄取调节蛋白）是一种细菌全局调节剂，它使用铁作为辅因子与特定的DNA序列结合。已经提出金属结合诱导蛋白质的构象变化，其随后能够识别DNA。在此已经通过质谱监测的选择性化学修饰研究了这种激活机制。首先，研究了Fur蛋白的每个赖氨酸残基的反应性，以蛋白的apo形式，然后在金属激活后，最后在与DNA结合之后。特别令人感兴趣的是Lys76，它在目标DNA存在下被高度保护免受修饰。进行了氢-氘交换实验，以更高分辨率绘制由金属结合引起的构象变化。基于这些结果，结合二级结构预测，提出了在Fur中存在非经典的螺旋-转-螺旋基序。实验结果表明，金属结合后的激活诱导了该特定基序的构象修饰。直接与DNA的主要凹槽相互作用的识别螺旋将包含域[Y55-F61]。在此螺旋之后，将在两条含有Lys76的β链之间形成一个小的“翼”，该翼可能直接与DNA相互作用。这些结果表明，Fur和另一种细菌阻遏物DtxR（白喉毒素阻遏物）不仅具有铁浓度调节剂的功能，还具有其DNA结合结构域的结构。 （C）2001学术出版社。 [参考：33]

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