酶加工的单分子动力学区分了线性和交叉链接的酸糖基质
Yongki Choi1, Issa S Moody, Patrick C Sims
1Institute for Surface and Interface Science, University of California, Irvine, California 92697, USA.
Journal of the American Chemical Society
|January 14, 2012
概括
T4溶酶在丁糖基质上表现出过程性和非生产性运动. 酶活性受到基质交叉连接的显著影响,影响其动态行为和基质相互作用.
科学领域:
- 生物化学 生物化学
- 酶学 是一种酶学.
- 单分子生物物理学的单分子生物物理.
背景情况:
- T4溶酶是细菌体T4复制中的关键酶,参与降解糖.
- 了解酶过程性和基质相互作用对于酶机制研究至关重要.
- 之前的研究经常面临由于光学方法 (如火和漂白) 的限制.
研究的目的:
- 为了研究单个T4溶酶分子的动态过程性.
- 为了比较T4溶酶在线性与交联丁糖基质上的行为.
- 开发和使用一种新的电子技术,用于长期单分子监测.
主要方法:
- 使用一种新的电子技术,单分子监测T4溶酶.
- 通过pyrene链接器将lyszyme连接到单壁碳纳米管场效应晶体管.
- 通过诱导电子信号测量基板驱动的曲运动.
主要成果:
- 在两个基板上,Lysozyme显示了20-50秒的过程性转换率和快速的非生产性运动 (200-400秒).
- 非生产性结合占用了与交叉链接酸甘的酶时间的43%,与线性基质的7%相比.
- 酶水解键与线性基质的末端结合,但在野生型基质中回避了交叉链接.
结论:
- T4溶酶的动态过程性受到二醇糖交叉链接的显著影响.
- 这种新型的电子技术使得单分子酶研究能够长时间,不受阻碍地进行.
- 酶-基质相互作用是复杂的,酶根据基质结构调整其催化策略.
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