碰撞诱导解离下二甲胺衍生多肽的碎裂特征研究  

Fragmentation Features of Dimethylamine-Derivatized Peptides Using Collision-Induced Dissociation

作　　者：邹伦妃 肖琛 熊淼 张启伟 郑琦[1] ZOU Lun-fei;XIAO Chen;XIONG Miao;ZHANG Qi-wei;ZHENG Qi(Key Laboratory of Optoelectronic Chemical Materials and Devices of Ministry of Education,Jianghan University,Wuhan 430056,China)

机构地区：[1]江汉大学光电化学材料与器件教育部重点实验室,湖北武汉430056

出　　处：《质谱学报》2023年第4期486-495,I0002,共11页Journal of Chinese Mass Spectrometry Society

基　　金：国家自然科学基金项目(21976069);江汉大学科技创新专项(2021KJZX002)。

摘　　要：串联质谱技术可以测定蛋白质酶解产物的分子质量、定位修饰位点、获取氨基酸序列信息等,已成为蛋白质组学领域的重要分析手段。鉴于酸性氨基酸能够在串联质谱分析中对多肽的裂解过程产生重要影响,本文通过二甲胺将多肽的羧基酰胺化,从而改变肽段在碰撞诱导解离模式下的碎裂特征。较未衍生多肽而言,被衍生多肽既可以产生特征性碎片离子,例如m/z 129.10/135.14,也易于产生种类更丰富的a、b、y、z离子。此外,羧基的中性化可在一定程度上抑制磷酸化多肽的中性丢失。这些特点使得基于羧基酰胺化的衍生方法有望展现在肽段表征分析方面的应用价值。Proteins are the carriers of biological structure and function,which are involved in almost all the physiological processes in organisms.The qualitative and quantitative analysis of proteins can not only help us understand the mechanisms of life activities,but also screen for the proteins with abnormal expression compared to healthy controls as biomarkers of diseases as well as environmental exposure to harmful substances,thus facilitating to unravel the mechanisms of disease generation and development.Tandem mass spectrometry(MS/MS)is currently the main tool for high-throughput proteomics analysis.It can characterize the proteins by determining the molecular mass of digestion products,locating modification sites,and obtaining sequence information.However,acidic amino acid residues often have a significant impact on the cleavage process of peptides,limiting the performance of MS/MS.For example,for the phosphopeptides containing abundance of negatively charged carboxyl and phosphoryl groups,their ionization is not efficient in the positive mode,and neutral loss is easy to occur during the cleavage process,resulting in a low coverage of product ions in the MS/MS spectra.In this paper,the carboxyl groups from the R group of aspartic acid and glutamic acid as well as the C-terminus of peptide were neutralized using dimethylamine derivatization under mild condition.Accordingly,the fragmentation features of peptides with altered charge properties were studied in collision-induced dissociation(CID)mode.Further,the peptides were labeled using light and heavy isotopic dimethylamine,respectively,thus enabling to verify the features based on the same ion with different labels.The results showed that the precursor ion signal from the derivatized peptide was significantly enhanced compared to that of the native peptide.And,the derived peptides could yield a variety of a,b,y,and z ions,and some reported ions in MS/MS analysis,such as the ion at m/z 129.10/135.14 produced by the peptides with glutamic acid or lysine residue at

关 键 词：多肽 酰胺化 碰撞诱导解离 串联质谱 

分 类 号：O657.63[理学—分析化学]