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用分子动力学,自由能量计算和序列分析分析Sem-5 SH3域及其连接体之间的相互作用
1Graduate Group in Biophysics, Department of Cellular and Molecular Pharmacology, University of California, San Francisco, California 94143, USA.
Journal of the American Chemical Society
|July 18, 2001
概括
Sem-5 SH3 域结合了富含的序列,但可以接受其他残留物. 范德瓦尔斯相互作用和新的VC值有助于预测结合特异性,并确定蛋白相互作用的关键残留物.
科学领域:
- 分子生物学分子生物学
- 生物化学 生物化学
- 计算化学的计算化学
背景情况:
- 在Caenorhabditis elegans的Src-homology-3 (SH3) 域中,Sem-5蛋白通常会结合富含proline的序列.
- 新出现的证据表明,SH3域可以容纳除了仅仅是prolines之外的胺N替代残留物,基于除侧链形状或刚性之外的其他因素.
研究的目的:
- 使用计算方法研究Sem-5 SH3域及其连接体之间的相互作用.
- 评估各种连接体替代的结合自由能量,并确定特异性和亲和性的关键残留物.
主要方法:
- 用分子动力学 (MD) 模拟和自由能量计算 (MM/PBSA) 来研究Sem-5-子相互作用.
- 使用了一种计算原子部分电荷的新方法,AM1-BCC,并与传统的RESP电荷进行了比较.
- 序列分析和范德瓦尔斯相互作用能量概况被生成以了解约束决定因素.
主要成果:
- 使用MM/PBSA与AM1-BCC电荷计算的相对结合的自由能量与实验数据有很好的相关性.
- AM1-BCC收费为分子模拟提供了RESP收费的更快替代方案,提高了药物设计的效率.
- 范德瓦尔斯相互作用被确定为确定在特定连接体位点的残留偏好 (N-与卡尔法替代) 的关键因素.
- 一个新的指标,VC值,有效地确定了Sem-5中负责结合特异性和亲缘性的关键残留物 (例如N190,N206).
结论:
- 这项研究证实,Sem-5 SH3域相互作用受到范德瓦尔斯力的控制,影响了连接体选择性.
- 在药物设计中,AM1-BCC收费计算方法为自由能量计算提供了高效和准确的方法.
- VC值为识别蛋白质 - 配体和蛋白质 - 蛋白质相互作用中的关键残留物提供了一个有希望的工具.
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