具有α-基拉,芳香侧链的类寡合体:链长度对二次结构的影响
C W Wu1, T J Sanborn, R N Zuckermann
1Department of Chemical Engineering, Northwestern University, Evanston, Illinois 60208, USA.
Journal of the American Chemical Society
|July 18, 2001
概括
基拉尔类 (N替代的甘氨酸) 寡合体形成稳定的螺旋. 它们的螺旋结构和二次形状取决于链条的长度,稳定的螺旋形成约13个残留物.
科学领域:
- 超分子化学 超分子化学
- 有机化学 有机化学
- 生物材料科学 生物材料科学
背景情况:
- 替代N的甘氨酸 (类) 可以形成稳定的螺旋体,而无需脊柱性或键.
- 螺旋稳定性受到硬体回避和静电排斥的影响.
- 螺旋表现出明显的圆形二元化 (CD) 光谱,类似于类α螺旋.
研究的目的:
- 研究寡合体长度,度和温度对有机溶性类同类寡合体的性二次结构的影响.
- 为了确定稳定的peptoid螺旋形成所需的最小链长.
- 为了评估这些状螺旋在溶液中的聚合行为.
主要方法:
- 使用循环二元化 (CD) 光谱学的系统研究.
- 合成和分析 (R) -N- ((1-phenylethyl) glycine (Nrpe) 寡合体,其长度从3到20个单体.
- 改变寡合体度和温度以观察结构变化.
主要成果:
- 在4至12个残留物之间的Nrpe寡合物中,观察到CD光谱特征的显著演变.
- 这种光谱变化归因于具有 cis/trans amide 键的链长度依赖的适配体群.
- 稳定的聚烯 (Nrpe) 螺旋需要至少约13个残留物的链长.
- Nrpe六合体没有显示任何度依赖的CD变化,表明溶液中的单体行为.
结论:
- 类螺旋体的形成和稳定性严重依赖于寡合体链长度.
- 观察到的CD光谱变化反映了与胺键配置相关的二级结构的过渡.
- 这些发现对于设计具有稳定的螺旋结构的生物模拟类动物至关重要.
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