谷胱甘肽的宽频太赫兹光谱研究  

Broadband Terahertz Spectroscopy of Glutathione

作　　者：郭聪 朱中杰 沈建雄 张宗昌 张建兵 赵德明[1] 赵红卫[2,3] GUO Cong;ZHU Zhong-Jie;SHEN Jian-Xiong;ZHANG Zong-Chang;ZHANG Jian-Bing;ZHAO De-Ming;ZHAO Hong-Wei(College of Chemical Engineering,Zhejiang University of Technology,Hangzhou 310014,China;Zhangjiang Laboratory,Shanghai Advanced Research Institute,Chinese Academy of Sciences,Shanghai 201210,China;Shanghai Institute of Applied Physics,Chinese Academy of Sciences,Shanghai 201800,China)

机构地区：[1]浙江工业大学化工学院,杭州310014 [2]中国科学院上海高等研究院张江实验室,上海201210 [3]中国科学院上海应用物理研究所,上海201800

出　　处：《分析化学》2020年第10期1367-1374,共8页Chinese Journal of Analytical Chemistry

基　　金：中国科学院微观界面物理与探测重点实验室项目和国防科技创新特区项目资助。

摘　　要：谷胱甘肽(Glutathione)的构型构象对其发挥生物学功能具有重要意义。本研究利用空气等离子体太赫兹时域光谱(THz-TDS)获得了还原型谷胱甘肽(GSH)和氧化型谷胱甘肽(GSSG)在0.5~12.0 THz波段的吸收光谱,结果表明,GSH在太赫兹波段有丰富的特征吸收峰,而GSSG呈现单调无特征的吸收曲线。粉末X射线衍射(PXRD)结果表明,GSH具有一定的晶型结构而GSSG为无定形态,提示太赫兹光谱对物质晶体结构有敏感响应。利用密度泛函理论(DFT)对GSH晶胞结构进行计算和太赫兹振动光谱分析,结果表明,GSH分子能形成丰富的氢键,这些氢键网络有助于约束柔性肽分子并使分子有序地堆叠形成晶体。晶格和氢键与太赫兹波作用产生共振吸收,GSH的太赫兹光谱中不同吸收峰对应分子不同集体振动或局域振动,并且与氢键的振动密切相关。本研究结果有助于加深GSH分子构型构象和分子弱相互作用的认识。The conformation of glutathione is of great significance for its biological function.In this study,the absorption spectra of reduced(GSH)and oxidized(GSSG)glutathione in the frequency range of 0.5-12 THz were obtained by the air plasma terahertz time-domain spectroscopy(THz-TDS).The results demonstrated that GSH had rich characteristic absorption peaks in the THz region,while GSSG presented a monotonous absorption spectrum without obvious peaks.Combined with powder X-ray diffraction(PXRD),GSH had a certain crystal structure and GSSG was amorphous,suggesting that the THz spectroscopy was sensitive to the molecular structure and crystal form.The density functional theory(DFT)calculation based on the GSH crystal structure was performed to simulate the THz absorption spectrum and analyze the vibrational property.The result showed that GSH molecule could form rich intra-and inter-molecular hydrogen bonds,which helped to constrain flexible peptide.Lattice vibration and hydrogen bonding of GSH can effectively resonate with THz waves.The different THz absorption peaks of GSH correspond to different collective or local molecular vibrations which were closely related to the hydrogen bonding interactions.The study may help to deepen the understanding of GSH molecular conformation and weak interactions.

关 键 词：宽频太赫兹光谱 还原型谷胱甘肽 氧化型谷胱甘肽 低频振动 氢键 

分 类 号：O657.3[理学—分析化学]