通过高极化 (1) H NMR 追踪活微生物的代谢
Piotr Dzien1,2, Anne Fages, Ghil Jona
1Klinik und Poliklinik für Nuklearmedizin, Technische Universität München , München 81675, Germany.
Journal of the American Chemical Society
|August 25, 2016
概括
这项研究表明,超极化1HNM可以追踪微生物中的酶活性,克服13CNM对代谢监测的限制.
科学领域:
- 生物化学
- 磁共振成像技术
- 代谢学
背景情况:
- 动态核极化 (dNP) 增强了核磁共振 (NMR) 在体内代谢监测的灵敏度.
- 由于放松时间短,直接超极化1H具有挑战性.
- 通过13C的间接1H超极化已经成为一个有前途的技术.
研究的目的:
- 通过13C超极化的1HNMR用于监测酶反应的实用性.
- 对微生物中的酸盐脱碳酶 (PDC) 和酸盐酸酶 (PFL) 的活性进行研究.
- 为了比较自发和J驱动的13C → 1H极化转移方法.
主要方法:
- 溶解动态核极化 (dDNP) 用于超极化.
- 在500 MHz的1H和13C核磁共振光谱.
- 在酵母和细菌中的酶反应的动态测量.
- 自发的异质核交叉放松和J驱动的极化转移.
主要成果:
- 在微生物中成功监测了PDC和PFL的pyruvate脱碳化.
- 13C NMR缺乏区分基板和产品的分辨率.
- 自发的13C → 1H转移使动力学研究成为可能,而J驱动的转移提供了更高的增强效果,但不适合动力学.
- 在酶反应过程中通过交叉放松增强了超极化13C1H信号.
结论:
- 与13C NMR相比,通过dDNP和13C偏振转移增强的1H NMR为特定的酶研究提供了更高的分辨率.
- 这种方法为微生物的实时代谢监测提供了一个敏感的方法.
- 这些基于1H的超极化技术在体内应用的潜力是显著的.
相关概念视频
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