两种异oprenoid合成酶的嵌合体在异oprenoid生物合成中催化所有四种合反应
Hirekodathakallu V Thulasiram1, Hans K Erickson, C Dale Poulter
1Department of Chemistry, University of Utah, 315 South 1400 East, Room 2020, Salt Lake City, UT 84112, USA.
Science (New York, N.Y.)
|April 7, 2007
概括
研究人员探索了异oprenoid化合物合成,专注于四个关键反应. 他们使用工程酶成功催化了分支和循环化,这表明这些关键的生物化学过程具有共同的进化起源.
科学领域:
- 生物化学 生物化学
- 酶学 是一种酶学.
- 有机化学 有机化学
背景情况:
- 在自然界中至关重要的异烯酸化合物是使用四种核心合反应构成的:链延长,环延长,分支和环延长.
- 虽然链延长和循环缩的酶是众所周知的,但负责分支和循环缩的酶仍然难以捉摸.
- 了解这些酶对于阐明各种异oprenoids 的完整生物合成途径至关重要.
研究的目的:
- 研究异oprenoid合反应的催化机制,特别是分支和循环化.
- 设计能够催化所有四种基本的异oprenoid 合反应的新酶.
- 探索参与异oprenoid生物合成的酶之间的进化关系.
主要方法:
- 通过将已知的链延长酶的部分替换为来自循环化酶的序列来构建嵌合蛋白质.
- 使用这些工程化学蛋白质,催化分枝和循环化反应.
- 立体化学和机械分析以描述新型酶的活性.
主要成果:
- 通过使用工程化基因蛋白质,成功催化了分支和循环化反应.
- 证明可以交换酶段来改变催化功能,从而实现新的反应途径.
- 提供了证据,证明了为以前未被描述的异oprenoid合反应创造酶的可行性.
结论:
- 这四种基本的异oprenoid合反应可以被工程酶催化,包括分支和循环结的酶.
- 立体化学和机械学数据表明,这四个酶家族可能是从一个共同的祖先酶进化出来的.
- 酶的催化部位的相对较小的改变可以解释各种合活动的演变.
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