在OxyR转录因子中氧化还原开关的结构基础
H Choi1, S Kim, P Mukhopadhyay
1Center for Cellular Switch Protein Structure, Korea Research Institute of Bioscience and, Biotechnology, P.O. Box 115, Yusong, 305-600, Taejon, South Korea
Cell
|April 13, 2001
概括
大肠杆菌OxyR转录因子
科学领域:
- 分子生物学分子生物学
- 结构生物学 结构生物学
- 生物化学 生物化学
背景情况:
- 大肠杆菌中的OxyR转录因子对于检测过氧化 (H2O2) 是至关重要的.
- OxyR激活涉及形成分子内二硫化键,这是一个关键的氧化还原敏感机制.
研究的目的:
- 阐明通过H2O2.2激活OxyR的结构基础.
- 以减少和氧化状态呈现OxyR调节域的晶体结构.
主要方法:
- 使用X射线结晶学来确定结构.
- 获得的分辨率:减少形式为2.7 Å,氧化形式为2.3 Å.
主要成果:
- 在还原状态下,氧化还原活性氨酸相距约为17 Å.
- 氧化导致二硫化键的形成和监管领域的重大结构改造.
- 这种结构变化改变了寡合体的关联,调解了氧化还原开关.
结论:
- 这项研究揭示了一种新的蛋白质调节机制,称为"折叠编辑".
- 在折叠域内可逆的二硫化物键形成动态控制OxyR功能.
- 这为OxyR如何应对氧化应激提供了详细的分子理解.
相关概念视频
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