小质子的连续化
Dengfeng Liu1, Thomas Wyttenbach, Perdita E Barran
1Department of Chemistry and Biochemistry, University of California at Santa Barbara, Santa Barbara, California 93106, USA.
Journal of the American Chemical Society
|July 10, 2003
概括
水分子在小上和在更高的电荷状态下更强烈地与第一个质子化位点结合. 结合强度随着随后的水分子的减少而降低,对于含有氨酸的酸,结合强度较弱.
科学领域:
- 物理化学 物理化学
- 计算化学计算化学
- 生物物理学的生物物理.
背景情况:
- 了解酸水化对于药物设计和蛋白质折叠等领域至关重要.
- 溶液中的质子与水分子相互作用,影响它们的结构和行为.
研究的目的:
- 为了研究水分子对质子化的连续结合.
- 量化水结合能,并确定化的趋势.
主要方法:
- 使用电子喷射电离和漂移细胞技术进行平衡实验.
- 实验数据与化结构的分子力学模拟进行比较.
主要成果:
- 水的结合能量在7-15 kcal/mol之间,第一个水分子结合最强.
- 更小的和更高的电荷状态表现出更强的初始水结合.
- 水与氨基基组相比,与质子化瓜尼迪诺基团 (氨酸) 的结合较弱.
- 水添加高度依赖于质电荷状态,弱于质序列.
结论:
- 的初始水化是由质子化部位的强烈相互作用主导的.
- 随着溶解的形成,随后的水分子的结合不那么强,可以与远程站点相互作用.
- 质电荷状态和大小显著决定了水合模式和结合亲和力.
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