从分子动力学模拟和对接实验中确定β-分泌酶的活性位子质子化状态:对基于结构的抑制剂设计的影响
1School of Chemistry and Molecular Engineering, and Center for Molecular Catalysis, Seoul National University, Seoul 151-747, South Korea. hwangseo@snu.ac.kr
Journal of the American Chemical Society
|December 25, 2003
概括
在阿尔茨海默病中至关重要的Memapsin 2 (BACE) 具有模两可的酸质子化状态. 模拟显示Asp228,而不是Asp32,作为抑制剂的键受体,指导药物设计.
科学领域:
- 生物化学 生物化学
- 神经科学是一个神经科学.
- 药物发现 药物发现 药物发现
背景情况:
- 梅马辛2 (BACE) 是一种β-分泌酶,参与β-粉样的产生,这是阿尔茨海默氏症发病的关键因素.
- 在BACE中催化酸残留物 (Asp32和Asp228) 的精确质子化状态对于其酶活性至关重要,但仍然模两可.
- 了解这些质子化状态对于开发有效的BACE抑制剂至关重要.
研究的目的:
- 用分子动力学模拟来确定Memapsin 2 (BACE) 中Asp diad的首选质子化状态.
- 阐明Asp32和Asp228在与强抑制剂结合中的作用.
- 为新型BACE抑制剂的基于结构的设计提供见解.
主要方法:
- 两个独立的分子动力学 (MD) 模拟BACE与抑制剂OM99-2复合.
- 分析抑制剂和活性部位残留物之间的键形成和稳定性.
- 用一种新型强效抑制剂进行对接实验,以评估能量和结构特征.
主要成果:
- 医学模拟表明,Asp32是中性的,Asp228是有离子的,以保持与抑制剂的基团的强键.
- 这种质子化状态在能量和结构上是有利的,与X射线晶体结构一致.
- 对接研究证实了这些发现,表明Asp228充当主要键受体.
结论:
- 这项研究表明,Asp228,而不是Asp32,可以作为BACE抑制剂的关键键受体.
- 这一发现对基于结构的设计和发现针对BACE的新阿尔茨海默病治疗方法具有重大意义.
- 澄清BACE活性部位残留物的质子化状态对于优化抑制剂疗效至关重要.
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