状螺旋中形状异质性的起源由基拉N-1-乙烯侧链形成的状螺旋
Sarah Alamdari1, Jim Pfaendtner1
1Department of Chemical Engineering, University of Washington, Seattle, Washington 98195, United States.
The journal of physical chemistry. B
|June 28, 2023
概括
状多类 (N替代的甘氨酸) 呈现出复杂的螺旋折叠. 这项研究揭示了Nspe和Nrpe类型喜欢相反的螺旋手性,与之前的计算模型相反,具有小的自由能量驱动力用于螺旋组装.
科学领域:
- 生物模拟化学是生物模拟化学.
- 聚合物科学 聚合物科学
- 计算化学是一种计算化学.
背景情况:
- 具有奇拉侧链的N替代型甘氨酸 (多类) 模仿自然的α螺旋.
- 实验研究表明,特定的反体形成不同的螺旋双手 (例如,Nspe右手,Nrpe左手).
- 以前的计算方法无法复制这些观察到的螺旋偏好.
研究的目的:
- 调查关于状螺旋折叠的实验观测和先前的计算发现之间的差异.
- 阐明治理性多类的立体选择螺旋偏好的基本原则.
- 为各种类侧链提供准确的计算预测.
主要方法:
- 使用量子力学 (DFT) 和分子力学计算对Nspe和Nrpe寡合体.
- 采用元动力学模拟来研究水性环境中的类折叠.
- 在其他实验性表征的类侧链 (N(r/s) sb,N(r/s) tbe,N(r/s) npe) 上执行了DFT计算.
主要成果:
- Nspe和Nrpe寡合物优先分别形成左侧和右侧螺旋体,与DFT和分子力学结果保持一致.
- 螺旋组件的自由能量障碍是最小的 (大约kBT),表明容易的形状变化.
- 更坚固的状侧链 (tbe,npe) 呈现出螺旋偏好,而不是较不坚固的 (pe,sb),其中 (S) -tbe倾向于右手和 (R) -tbe倾向于左手螺旋.
结论:
- 这项研究解决了性多型螺旋体的计算建模中的差异.
- 识别了小型自由能量差异,这些差异决定了peptoids中的螺旋手性.
- 为预测和设计基于侧链化学的特定螺旋性质的形结构提供了一个框架.
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