一个合规交换机触发了酶保护,防止Shethna蛋白II (FeSII) 的氧气损伤
Julia Schlesier1, Michael Rohde1, Stefan Gerhardt1
1Institute for Biochemistry, Albert-Ludwigs-Universität Freiburg , Albertstrasse 21, 79104 Freiburg, Germany.
Journal of the American Chemical Society
|December 15, 2015
概括
通过对谢特纳蛋白II (FeSII) 的氧化还原依赖性构造变化,实现了对酶的保护. 这种机制保护有氧细菌的固定.
科学领域:
- 生物化学
- 结构生物学
- 微生物学
背景情况:
- 酶可催化 prokaryotes 中必需的固定,但对氧气敏感.
- 在有氧环境中需要强大的机制来保护酶.
- 谢特纳蛋白II (FeSII) 与酶组分形成一个保护性复合体.
研究的目的:
- 为了确定Azotobacter vinelandii FeSII的三维结构
- 阐明依赖氧气的酶保护的分子基础.
- 模拟酶的结构保护的三元复合体.
主要方法:
- 在2.1 Å分辨率下进行X射线衍射以确定FeSII结构.
- 生产和分离亚菌维尼兰迪FeSII.
- 用于检测FeSII结合和相互作用的保护试验.
主要成果:
- 双重FeSII蛋白质结构显示了两个不同的构造状态.
- 在铁硫团附近的延伸循环的氧化还原依赖重新排列被确定.
- 在激活时,FeSII通过静电相互作用与酶复合体结合.
结论:
- 在FeSII中发现的形状变化为依赖氧的酶保护提供了分子基础.
- 在氧气存在的情况下,FeSII在维持酶功能方面发挥着至关重要的作用.
- 一个涉及FeSII的化酶受保护三元复合物的模型被提出.
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