银离子促进神经传导素分子内氢原子转移和C-C键解离反应  

Single Silver Ions Facilitate Intramolecular Hydrogen Atom Transfer and C−C Bond Dissociation of Neurotransmitters

作　　者：易秋浩 吴海铭 骆智训[1,2] Qiuhao Yi;Haiming Wu;Zhixun Luo(State Key Laboratory for Structural Chemistry of Unstable and Stable Species,Institute of Chemistry,Chinese Academy of Sciences,Beijing 100190,China;School of Chemistry,University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院化学研究所分子动态与稳态结构国家重点实验室,北京100190 [2]中国科学院大学化学科学学院,北京100049

出　　处：《Chinese Journal of Chemical Physics》2024年第2期341-350,I0104,共11页化学物理学报（英文）

基　　金：This work was supported by the National Natural Science Foundation of China(No.92261113 and No.21722308);Key Project of Frontier Science Research of Chinese Academy of Sciences(QYZDB-SSWSLH024).

摘　　要：色氨酸、酪氨酸和组氨酸是三种基本的氨基酸,也是大脑营养代谢中重要神经传导素的前驱体。本文利用自制的反射式时间飞行质谱仪结合磁控溅射束源和下联管式反应器,在气相条件下研究了这三个氨基酸与银离子的相互作用,揭示了这些有机小分子在银离子的存在下容易解离并产生碎片和产物重组的现象,并利用密度泛函理论计算,阐明了其中的反应机制。研究发现,银离子能促进氢原子转移,进而影响竞争性的C_(α)-C_(β)和C_(β)-C_(γ)键解离反应。本研究丰富了对这类神经传导素分子基本规律与性质的精准认识,从而有助于深入理解生物体内类似生理过程的化学机制。Tryptophan(Trp),tyrosine(Tyr),and histidine(His),known as three essential amino acids,are also precursors of vital neurotransmitters in brain nutrient metabolism.In this study,we have conducted a gas-phase study on their interactions with silver ions by a customized reflectron time-of-flight mass spectrometer combined with a magnetron sputtering source and a downstream flow tube reactor.It is unveiled that these physiological molecules are readily dissociated in the presence of Ag^(+)ions,giving rise to fragmentation and recombination products.Utilizing density functional theory calculations,we have clarified the reaction mechanism of the dissociative process.It is found that the silver ions facilitate the hydrogen atom transfer reaction followed by competitive C_(α)−C_(β) and C_(β)−C_(γ) bond dissociation.This study enriches the basic and precise properties of such neurotransmitter molecules and helps us understand similar physiological mechanisms in vivo.

关 键 词：神经传导素 色氨酸 金属-有机相互作用 C-C键解离 质谱 

分 类 号：O621.25[理学—有机化学]