抗水溶剂效应:一种实验探测器,用于测量水作用对酶抑制剂结合的作用
Paul A Bartlett1, Naeem Yusuff, Alice C Rico
1Department of Chemistry, University of California, Berkeley, California 94720-1460, USA. paul@fire.cchem.berkeley.edu
Journal of the American Chemical Society
|April 11, 2002
概括
这项研究使用不同的溶剂成分研究了对酶抑制剂结合的疏水效应. 结果表明,增加乙醇度显著提高了结合亲和力,提供了对蛋白质 - 配体相互作用的见解.
科学领域:
- 生物化学 生物化学
- 化学生物学 化学生物学
- 酶动力学 酶动力学
背景情况:
- 了解蛋白质 - 配体相互作用对于药物发现至关重要.
- 疏水效应在分子结合中起着重要的作用.
- 热解是一种与生物过程相关的类酶.
研究的目的:
- 量化酸盐和胺酸抑制剂对热解的结合亲和力中的疏水性贡献.
- 开发一种实验方法来区分溶解效应与其他约束影响.
- 为了将观察到的疏水效应与隔离的疏水表面积相关联.
主要方法:
- 在不同乙醇缓冲溶剂组合 (0-9%乙醇) 中,研究了抑制剂对热解的结合亲和力.
- 测量抑制常数 (K(i)) 来评估结合强度.
- 分析了溶剂组成和结合亲和力之间的关系.
主要成果:
- 缓冲溶液中乙醇度的增加导致抑制常数 (K(i)) 增加了多达一个数量级.
- "抗效应"的大小与在抑制剂-酶协会上埋葬的水表面积相关.
- 与基于乙醇-水混合物表面张力的预测相比,观察到的效应减弱了.
结论:
- 这项研究提供了一种实验方法,用于剖析蛋白质 - 配体结合中的溶解效应.
- 结果支持Lum-Chandler-Weeks理论关于疏水效应的大小依赖.
- 疏水性相互作用显著影响抑制剂与热解的结合亲和力.
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