在酶抑制动力学中,分子噪声诱导的激活剂-抑制剂双重性
1Department of Chemistry, Indian Institute of Technology, Madras, Chennai 600036, India.
The Journal of chemical physics
|October 16, 2023
概括
酶抑制中的分子噪声揭示了令人惊的激活剂-抑制剂二元性. 在过渡状态下,酶抑制剂可以意外地增强活性,挑战经典动力学.
科学领域:
- 生物化学 生物化学
- 化学动力学 化学动力学
- 生物物理学的生物物理.
背景情况:
- 经典的酶抑制动力学预测,随着抑制剂度的增加,活性单调下降.
- 这些理论往往忽略了在介光酶度下的分子噪声.
- 了解噪声效应对于准确建模酶机制至关重要.
研究的目的:
- 开发一种对酶抑制动力学的随机概括.
- 研究分子噪声在竞争性和非竞争性抑制中的作用.
- 为了揭示非经典的行为,如激活器-抑制器二元性.
主要方法:
- 酶抑制机制的随机建模.
- 暂时和稳定状态动力学的分析.
- 引入统计措施,包括一个随机的Lineweaver-Burk图.
- 分数酶活性和等待时间相关性的量化.
主要成果:
- 在过渡疗法中观察到非经典的激活剂-抑制剂二元性,其中抑制剂可以增强酶活性.
- 统计测量显示,分量酶活性和等待时间的非单调反应与抑制剂度的增加有关.
- 动态相位图说明了这种二元性的条件,与分子记忆效应有关.
结论:
- 分子噪声在酶抑制中引入了非经典的行为,特别是瞬态状态中的激活剂-抑制剂二元性.
- 观察到的二元性与分子记忆有关,其特点是产品周转时间的正相关性.
- 随着分子记忆效应的消失,在稳定状态下恢复经典结果.
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