盐桥稳定在气相中充电的zwitterionic arginine聚合物的盐桥稳定
R R Julian1, R Hodyss, J L Beauchamp
1Beckman Institute, California Institute of Technology, Pasadena, CA 91125, USA.
Journal of the American Chemical Society
|July 27, 2001
概括
研究人员发现了由盐桥形成的稳定氨酸聚合物. 这些与各种离子观察到的非共价复合体,表现出独立于反体纯度的稳定性,循环体是非常稳定的.
科学领域:
- 生物化学 生物化学
- 化学物理 化学物理
- 质谱测量质量谱测量
背景情况:
- 氨酸是一种基本的氨基酸,在生物系统中起着至关重要的作用.
- 了解氨基酸的非共价相互作用对分子生物学和药物设计至关重要.
研究的目的:
- 研究氨酸聚合物的形成和稳定性.
- 描述控制氨酸集群稳定性的非共价相互作用.
- 探索离子和反体纯度对阿金氨酸聚合物稳定性的影响.
主要方法:
- 四极离子陷质谱法用于检测和分析氨酸聚合物.
- 用B3LYP/6-31G级的密度函数理论 (DFT) 计算来建模结构和能量.
- 使用D-氨酸和同位素标记的L-氨酸混合物的实验评估了反体效应.
主要成果:
- 发现了异常稳定的氨酸分子间结合的聚合物.
- 观察到稳定的非对应性复合体的阿尔金因在它的zwitterionic状态,通过盐桥与或离子相互作用.
- 确定了与各种离子 (Na+, K+, Li+, Mg2+, Cl-, F-, Br-, I-, NO3-) 组成的氨酸.
- 氨酸的循环修剪器,特别是那些用化物或酸盐覆盖的,表现出了特殊的稳定性.
- 发现聚合物稳定性独立于氨酸反体纯度.
结论:
- 素很容易形成由分子间盐桥稳定稳定的稳定聚合物.
- 氨酸的zwitterionic性质有助于形成强大的非共价复合体,具有一系列无机离子.
- 特定的结构,如循环剪切器,表现出了显著的稳定性,为分子自我组装提供了洞察力.
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