在晶体中,在MauG/前甲基胺脱酶复合体内的翻译后修饰
Lyndal M R Jensen1, Ruslan Sanishvili, Victor L Davidson
1Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA.
Science (New York, N.Y.)
|March 13, 2010
概括
MauG酶通过修改托残留物来产生甲基胺脱酶 (MADH) 的TTQ辅因子. X射线结晶学揭示了MauG-preMADH复合物的结构细节和催化能力.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 酶学 是一种酶学.
背景情况:
- 甲基胺脱酶 (MADH) 需要三三基 (TTQ) 辅因子进行活性.
- MauG 是一种二酶,对托残留物进行翻译后修改以形成TTQ辅因子至关重要.
研究的目的:
- 阐明MauG介导的TTQ辅因子合成的结构基础.
- 研究MauG与其基质preMADH复合的催化机制.
主要方法:
- 使用X射线晶体学以2.1安格斯特罗姆分辨率确定MauG-preMADH复合物的结构.
- 通过监测添加过氧化后的TTQ合成,进行了催化活性测试.
主要成果:
- 晶体结构揭示了c型铁与TTQ前体位点之间的显著距离,这意味着远程电子转移.
- 在其中一个血红组中观察到非典型的His-Tyr轴结.
- MauG-preMADH复合体证明了催化能力,在过氧化的存在下发生了依赖MauG的TTQ合成.
结论:
- 结构和功能数据提供了对电子转移路径和MauG.独特的结合的洞察力.
- 在其晶体复合体中,MauG具有催化活性,支持其在TTQ辅因子形成中的作用.
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