一种非天然的氨基酸,可诱导β叶折叠和酸相互作用
James S Nowick1, Kit S Lam, Tatyana V Khasanova
1Department of Chemistry, University of California Irvine, Irvine, California 92697-2025, USA. jsnowick@uci.edu
Journal of the American Chemical Society
|May 2, 2002
概括
一种新型的氨基酸,Orn(i-PrCO-Hao),使能够形成β片结构和二元化. 这种独特的氨基酸充当,在不改变序列的情况下诱导结构,促进受控的折叠和相互作用.
科学领域:
- 类化学 类化学
- 生物分子工程 生物分子工程
- 有机合成 有机合成
背景情况:
- 二次结构,如β片,对于蛋白质的功能至关重要.
- 设计具有可预测结构和自我组装特性的仍然是一个挑战.
- 诱导β-sheet结构的现有方法可能涉及显著的序列修改.
研究的目的:
- 引入一种新型氨基酸衍生物,Orn(i-PrCO-Hao),用于诱导中的β-片状结构.
- 通过使用标准合成方法,证明Orn(i-PrCO-Hao) 很容易被纳入序列.
- 研究加入Orn(i-PrCO-Hao) 对的折叠和二聚化的结构后果.
主要方法:
- 合成Orn ((i-PrCO-Hao) 和其Fmoc受保护的衍生物.
- 自动化Fmoc固体相合成以结合新型氨基酸.
- 核磁共振 (NMR) 光谱 (横向-ROESY,合常数,化学转移) 用于分析的结构和形状.
主要成果:
- 该Fmoc-Orn(i-PrCO-Hao) -OH衍生物已成功合成并纳入.
- 4内部含有Orn(i-PrCO-Hao),在CDCl3.3.中形成了一个二维β片状结构.
- 五,与N端的Orn(i-PrCO-Hao),折叠,但没有在CD3OD中二元化.
- Orn ((i-PrCO-Hao) 作为一个结构,诱导β片的形成与最小的序列干扰.
结论:
- 新型氨基酸Orn(i-PrCO-Hao) 有效诱导β片结构,并促进中的二分化.
- 这种氨基酸为设计具有特定二次结构和自我组装特性的提供了多功能工具.
- Orn ((i-PrCO-Hao) 提供了一种控制折叠的方法,而无需替代原生残留物,保留侧链功能.
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