蛋白质芳香基团的1H -13C HSQC 信号增强研究

波谱学杂志

蛋白质芳香基团的¹H -¹³C HSQC 信号增强研究

蒋先旺1,2，孙鹏 1,2，肖楠 1,2，蒋滨 1，秦显国1，李从刚1，刘买利1*，张许 1*

1. State Kay Laboratory of Magnetic Resonance and Atomic and Molecular Physics (Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences), Wuhan 430071, China;
2. University of Chinese Academy of Sciences, Beijing 100049, China

收稿日期:2013-05-28 修回日期:2013-06-05 出版日期:2014-03-05 发布日期:2014-03-05
作者简介:*通讯联系人：刘买利，电话：027-87197305，E-mail: ml.liu@wipm.ac.cn；张许，电话：027-87197056，E-mail: zhangxu@ wipm.ac.cn.
基金资助:
National Natural Science Foundation of China (20875098, 21075132), National Major Basic Research Program of China (2009CB918603), and the Ministry of Science and Technology of China (2009IM030700).

Sensitivity Enhancement in ¹H -13C HSQC Experiments on Aromatic Groups in Proteins

JIANG Xian-wang1,2，SUN Peng1,2，XIAO Nan1,2，JIANG Bin1，QIN Xian-guo1，LI Cong-gang1，LIU Mai-li1*，ZHANG Xu1*

1. 波谱与原子分子物理国家重点实验室（中国科学院武汉物理与数学研究所），湖北武汉 430071；
2. 中国科学院大学，北京 100049

Received:2013-05-28 Revised:2013-06-05 Online:2014-03-05 Published:2014-03-05
About author:JIANG Xian-wang(1984-), male, born in Hunan, specializing in NMR methodology and application. *Corresponding author: LIU Mai-li, Tel: +86-27-87197305, E-mail: ml.liu@wipm.ac.cn; ZHANG Xu, Tel: +86-27-87197056, E-mail: zhangxu@wipm.ac.cn.
Supported by:
National Natural Science Foundation of China (20875098, 21075132), National Major Basic Research Program of China (2009CB918603), and the Ministry of Science and Technology of China (2009IM030700).

摘要/Abstract

摘要：

Aromatic side chains are usually located in the hydrophobic core or ligand binding sites of proteins. They play important roles in protein functions such as structure stabilization and biological recognition through noncovalent interactions. Thus, aromatic side chains are considered to be a promising probe to determine the structure and dynamics of protein through NMR. However, they are not frequently studied in practice. One of the reasons is that some NMR
signals of aromatic rings are rarely observed due to the severely line broadening induced by complex slow internal motion. In this study, CPMG-INEPT ¹H-¹³C HSQC was employed to detect the aromatic resonances of protein GB1. It was found that some unobservable peaks in routine ¹H-¹³C HSQC spectrum could be recovered in the corresponding CPMG-INEPT ¹H-¹³C HSQC spectrum. This indicated that the CPMG-INEPT ¹H-¹³C HSQC may be an effective alternation to routine ¹H-¹³C HSQC for detecting the resonances of aromatic rings in proteins.

关键词: NMR, CPMG-INEPT, chemical exchange, sensitivity enhancement, aromatic side chain

Abstract:

含芳香环的氨基酸残基多处于蛋白质的疏水内核或者是蛋白质与配体的结合部位，这些残基间的非共价键相互作用对于蛋白质结构的稳定性和生物的特异性识
别有重要意义．因此，在蛋白质的核磁共振研究中，芳香基团被认为是一个研究蛋白质结构动力学的潜在探针．但是由于芳香基团的1H-13C HSQC谱的灵敏度较低，目前，利用核磁共振对其进行研究乏善可陈．造成这一现象的主要原因可能在于芳香环体积较大，往往存在慢的翻转运动，导致其NMR信号被展宽．作者利用CPMG-INEPT HSQC序列可以有效地减小慢运动影响的特征，将其应用到了GB1蛋白质芳香环的¹H-¹³CHSQC谱中，有效的增强了芳香基团HSQC谱信号的灵敏度，得到了部分在常规HSQC中无法观测的信号．

Key words: 核磁共振(NMR), CPMG-INEPT, 化学交换, 信号增强, 芳香环侧链

中图分类号:

O482.53

蒋先旺1,2，孙鹏 1,2，肖楠 1,2，蒋滨 1，秦显国1，李从刚1，刘买利1*，张许 1*. 蛋白质芳香基团的¹H -¹³C HSQC 信号增强研究[J]. 波谱学杂志.

JIANG Xian-wang1,2，SUN Peng1,2，XIAO Nan1,2，JIANG Bin1，QIN Xian-guo1，LI Cong-gang1，LIU Mai-li1*，ZHANG Xu1*.

Sensitivity Enhancement in ¹H -13C HSQC Experiments on Aromatic Groups in Proteins

[J]. Chinese Journal of Magnetic Resonance.

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蛋白质芳香基团的¹H -¹³C HSQC 信号增强研究

Sensitivity Enhancement in ¹H -13C HSQC Experiments on Aromatic Groups in Proteins

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