由氨基酸-tRNA蛋白转移酶形成基于蛋白质的键
Kazunori Watanabe1, Yukimatsu Toh, Kyoko Suto
1Institute of Biological Resources and Functions, National Institute of Advanced Industrial Sciences and Technology, 1-1-1, Higashi, Tsukuba-shi, Ibaraki 305-8566, Japan.
Nature
|September 25, 2007
概括
欧细菌的基/基-tRNA蛋白转移酶 (LF转移酶) 通过一种新的基于蛋白质的机制形成键. 一个电子继电系统促进了质子抽象,使核友性攻击能够形成键.
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:
- 欧细菌的基/基-tRNA蛋白转移酶 (LF转移酶) 催化了键的形成.
- 精确的LF转移酶的催化机制在很大程度上是未知的.
研究的目的:
- 为了阐明由LF转移酶形成键的催化机制.
- 为了确定LF转移酶活动的结构基础.
主要方法:
- 用X射线晶体学来确定复杂的结构.
- 现场定向的突变发生研究,以调查催化作用.
主要成果:
- 确定了LF转移酶复合体与基质和类型的结构.
- 一个涉及Asp 186和Gln 188的电子继电器被确定.
- 这种继电器有助于从受体的N端Arg中提取质子.
结论:
- 转酶采用一种基于蛋白质的催化机制,类似于血清蛋白酶酸化的逆转.
- 鉴定出来的机制解释了LF转移酶是如何产生核友的,从而形成键的.
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