甲基化域:对于线性格拉米西丁的非核糖体生物合成而言,它是必不可少的修饰酶
Georg Schoenafinger1, Nadine Schracke, Uwe Linne
1Fachbereich Chemie/Biochemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse, D-35032 Marburg, Germany.
Journal of the American Chemical Society
|June 8, 2006
概括
这项研究表明,N-形成对于通过非核糖体合成酶LgrA1.1启动格拉米西丁生物合成至关重要. 形式化域将甲基转移到瓦林,为链延长创造必要的起始单元.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 酶学 是一种酶学.
背景情况:
- N-形成是 prokaryotic 核糖体合成中的一个关键步骤.
- 在非核糖体合成 (NPS) 中,N-形成是不常见的,并且在很大程度上尚未被探索.
- 线性格拉米西丁非核糖体合成酶 (LgrA) 系统的初始步骤尚未完全理解.
研究的目的:
- 为了研究LgrA1模块的形式转移酶活性.
- 为了确定是否需要N-形成来启动格拉米西丁生物合成.
- 在NPS中识别新的定制酶.
主要方法:
- 在LgrA1模块对形式转移酶活性进行了体外测试.
- 测试甲基组从甲基四基酸盐 (fH4F) 转移到氨酸.
- 使用双模块LgrA系统进行长度测定,具有和没有形式基捐赠体.
主要成果:
- 假定LgrA1的形式化域成功地将形式基从N10-和N5-fH4F转移到瓦林.
- 甲基-氨酸被证实是格拉米西丁生物合成的基本起始单元.
- 延长试验显示,在没有甲基供体的情况下,没有二形成,但与甲基供体一起产生甲基--甘氨酸.
结论:
- LgrA的第一个域表现出形式转移酶活性,证实其在NPS中的作用.
- 这一发现在非核糖体合成途径中发现了一种新的定制酶.
- N-形成是gramicidin生物合成启动的关键,以前未被识别的步骤.
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