键合作性,振动合,以及螺旋稳定性的依赖于小3-10螺旋的氨基酸序列的变化. 一个密度函数理论的研究研究
Robert Wieczorek1, J J Dannenberg
1Department of Chemistry, City University of New York, Hunter College and the Graduate School, 695 Park Avenue, New York, NY 10021, USA.
Journal of the American Chemical Society
|November 13, 2003
概括
这项研究优化了五种螺旋和β链形状的五个五. 螺旋中的键表现出比其他相互作用更强的振动合,影响结构.
科学领域:
- 计算化学是一种计算化学.
- 分子建模分子建模
- 酸科学是一种科学.
背景情况:
- 酸采用各种二次结构,包括3(10) -螺旋和β-链.
- 了解这些结构的能量和振动特性对于预测的行为至关重要.
- 氨基酸序列显著影响的构成和稳定性.
研究的目的:
- 通过计算优化和比较五种特定五的3(10) 螺旋和开放β链构造.
- 研究不同氨基酸残留在特定位置的能量贡献.
- 在优化结构中分析振动合和键合作相互作用.
主要方法:
- 密度函数理论 (DFT) 计算使用B3LYP/D95级理论.
- 在3(10) - 螺旋和β-链形态中对五个的全几何优化.
- 振动频率分析以确认稳定的结构并研究振动合.
主要成果:
- 优化了GGGGG,GAGGG,GVGGG,GLGGG和GIGGG五的结构,以螺旋和β-链形式获得.
- 螺旋形状在能量方面比β-链更受青,相对能量范围从-2.1到-3.6千卡.
- 振动分析证实,通过螺旋体中的键链比通过空间或共价键更强的振动合.
结论:
- 对于研究的五,在能量方面更喜欢3(10) 螺旋形状.
- 氨基酸序列,特别是在第二个位置,调节螺旋结构的稳定性.
- 合作性键相互作用在稳定螺旋形状方面发挥着重要作用,这是振动合分析所证明的.
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