A study of the interaction between TMAO and urea in water using NMR spectroscopy.
A study of the interaction between TMAO and urea in water using NMR spectroscopy.
复制标题
使用核磁共振波谱研究水中 TMAO 和尿素之间的相互作用。
DOI：
10.1039/d2cp02475f
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
Nasralla M
中科院分区：
文献类型：
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作者：
Nasralla M
三甲胺 N-氧化物 (TMAO) 和尿素是有机生物小分子。 TMAO 被认为是一种保护性渗透剂，可促进生物分子的天然形式，而尿素是一种变性剂。了解TMAO和尿素对水结构的影响可能有助于揭示这种活性背后的分子机制。在这里，我们在 300 K 下使用 NMR 光谱研究了 TMAO-水、尿素-水和 TMAO-尿素-水的三元溶液。添加 TMAO 后发现水中的总氢键增强，并且这种影响被 1 份 TMAO 与 4 份尿素的摩尔比中和。研究发现尿素对水氢键网络的强度和水分子的动力学影响很小。有证据表明 TMAO 和尿素之间存在弱相互作用。总而言之，这些结果表明，TMAO 作为保护性渗透剂的功能及其对尿素的反作用可能是由其与水的氢键相互作用的强度以及水自身氢键网络的二次强化驱动的。他们还认为TMAO-尿素复合物是通过尿素提供氢键而形成的。
Trimethylamine N-oxide (TMAO) and urea are small organic biological molecules. While TMAO is known as a protective osmolyte that promotes the native form of biomolecules, urea is a denaturant. An understanding of the impact of TMAO and urea on water structure may aid in uncovering the molecular mechanisms that underlie this activity. Here we investigate binary solutions of TMAO–water, urea–water and ternary solutions of TMAO–urea–water using NMR spectroscopy at 300 K. An enhancement of the total hydrogen bonding in water was found upon the addition of TMAO and this effect was neutralised by a mole ratio of 1-part TMAO to 4-parts urea. Urea was found to have little effect on the strength of water's hydrogen bonding network and the dynamics of water molecules. Evidence was found for a weak interaction between TMAO and urea. Taken together, these results suggest that TMAO's function as a protective osmolyte, and its counteraction of urea, may be driven by the strength of its hydrogen bond interactions with water, and by a secondary reinforcement of water's own hydrogen bond network. They also suggest that the TMAO–urea complex forms through the donation of a hydrogen bond by urea.