通过基酶减少化环烯
Feng Ni1, Chi Chung Lee, Candy S Hwang
1Department of Chemistry, University of Southern California, Los Angeles, California 90089-0744, United States.
Journal of the American Chemical Society
|July 10, 2013
概括
酶 (N2ase) 减少3,3-二cyclopropene (DFCP),裂开碳-键形成和2-. 这表明N2酶.
科学领域:
- 生物化学 生物化学
- 酶学 是一种酶学.
- 有机金属化学 有机金属化学
背景情况:
- 酶 (N2ase) 是一种复杂的酶,对生物固定至关重要.
- 研究N2ase的基质范围揭示了其催化作用的多功能性.
- 化化合物通常是对生物还原的反抗性.
研究的目的:
- 为了研究由N2ase减少3,3-二cyclopropene (DFCP),第一个已知的含有素的基质,由N2ase.
- 阐明DFCP减少的机制和产品.
- 探索N2ase在C-F键裂解中的催化能力.
主要方法:
- 使用纯化N2ase组分 (MoFe和Fe蛋白) 的酶降解试验.
- 使用气体染色学-质谱学 (GC-MS) 和核磁共振 (NMR) 光谱学识别还原产品 (和2-) 2.
- 乳标记研究 (d2-DFCP) 以追踪反应途径和中间体.
主要成果:
- 在DFCP中,N2酶减少性地分裂了C-F键,产生了 (P1) 和二 (P2).
- 这两种产品都需要ATP和一种外源性减少剂 (dithionite),类似于N2减少.
- 标签表明CC键裂变,并揭示了还原中间体的几何约束.
结论:
- 酶具有减少碳-键裂解的能力.
- DFCP作为一种新型基质,扩大了已知的N2ase的催化谱.
- 这些发现突显了N2ase酶的显著和独特的酶能力范围.
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