确定酸氧化酶中酸胺中间体的动力能力
Michael P Valley1, Shane E Tichy, Paul F Fitzpatrick
1Department of Biochemistry and Biophysics emistry, Texas A&M University, College Station, Texas 77843-2128, USA.
Journal of the American Chemical Society
|February 17, 2005
概括
化物通过与flavin辅因子形成添加物来使化氧化酶失活. 这种反应发生在质子抽象后,在flavin氧化之前,在酶机制中捕获一种电友性中间体.
科学领域:
- 生物化学 生物化学
- 酶动力学 酶动力学
- 有机化学 有机化学
背景情况:
- 酸氧化酶是一种纤维蛋白催化酸氧化.
- 已知化物可以抑制各种酶.
研究的目的:
- 为了阐明化物对酸氧化酶的不活性化机制.
- 为了确定参与酶的催化循环的中间物种.
主要方法:
- 酶动力学研究研究酶动力学研究.
- 弗拉添加物的质谱法
- 动态同位素效应测量 动态同位素效应测量
主要成果:
- 化物通过flavin添加物形成 (乙/乙) 不活性化化氧化酶.
- 无活化发生在质子抽象后和黄素氧化之前,其动态同位素效应为7.9.
- 化物捕获了一个在酶机制中提出的电友中间体.
结论:
- 该机制涉及从基中提取质子,向黄素添加碳,消除酸盐,并形成电友性胺.
- 化物失活提供了证据,证明了这一拟议的机制,通过捕获一个关键的中间体.
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