贝塔转结构的键在D(2) O2中得到稳定
Younhee Cho1, Laura B Sagle, Satoshi Iimura
1Department of Chemistry, Texas A&M University, 3255 TAMU, College Station, Texas 77843, USA.
Journal of the American Chemical Society
|November 19, 2009
概括
弹性样多 (ELP) 的较低临界溶液温度 (LCST) 受水类型和二次结构的影响. 结合,而不是疏水性,驱动了ELP在重水 (D2O) 和轻水 (H2O) 中的崩.
科学领域:
- 生物化学 生化学
- 聚合物科学 聚合物科学
- 物理化学 物理化学
背景情况:
- 弹性类多 (ELP) 呈现较低的临界溶液温度 (LCST) 现象,这对于它们的刺激反应行为至关重要.
- 了解影响ELP阶段过渡的因素对于设计先进的生物材料和药物输送系统至关重要.
研究的目的:
- 调查ELP链长度和客残留化学物质在D2O和H2O中对LCST的影响.
- 为了将重水和轻水之间的LCST值差异与ELP链的二次结构形成联系起来.
主要方法:
- 在D2O和H2O中测量较低的临界溶液温度 (LCST).
- 循环二元化 (CD) 和红外 (IR) 光谱用于二次结构分析.
- 差异扫描热度计 (DSC) 用于热力学分析.
主要成果:
- 在D2O和H2O之间观察到LCST的显著差异,与二次结构相关.
- 形成更大的β-转/β-聚合结构的多体在H2O和D2O之间显示出更大的LCST转移.
- 这些特定的ELP被发现是最少的疏水性,表明疏水性的作用减少了.
结论:
- 与H2O相比,在D2O中稳定ELP的崩状态方面,结起的作用比疏水性更为关键.
- 二次结构形成,特别是β转和聚合物,是ELP对重水和轻水的差异反应的关键决定因素.
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