Characterization of Disulfide-Linked Peptides Using Tandem Mass Spectrometry Coupled with Automated Data Analysis Software

Disulfide bond formation is critical for maintaining structure stability and function of many peptides and proteins. Mass spectrometry has become an important tool for the elucidation of molecular connectivity. However, the interpretation of the tandem mass spectral data of disulfide-linked peptides has been a major challenge due to the lack of appropriate tools. Developing proper data analysis software is essential to quickly characterize disulfide-linked peptides. A thorough and in-depth understanding of how disulfide-linked peptides fragment in mass spectrometer is a key in developing software to interpret the tandem mass spectra of these peptides. Two model peptides with inter- and intra-chain disulfide linkages were used to study fragmentation behavior in both collisional-activated dissociation (CAD) and electron-based dissociation (ExD) experiments. Fragments generated from CAD and ExD can be categorized into three major types, which result from different S–S and C–S bond cleavage patterns. DiSulFinder is a computer algorithm that was newly developed based on the fragmentation observed in these peptides. The software is vendor neutral and capable of quickly and accurately identifying a variety of fragments generated from disulfide-linked peptides. DiSulFinder identifies peptide backbone fragments with S–S and C–S bond cleavages and, more importantly, can also identify fragments with the S–S bond still intact to aid disulfide linkage determination. With the assistance of this software, more comprehensive disulfide connectivity characterization can be achieved.

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纳升电喷雾串联质谱法确证阿托西班的一级结构

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西番莲中黄酮碳苷的串联质谱分析

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芍药苷的电喷雾串联质谱研究

采用电喷雾串联质谱(ESI-MSn)技术, 结合H/D交换方法, 在正、负离子检测模式下对白芍药材中主要成分芍药苷的质谱裂解规律进行了系统研究. 实验结果表明, 该化合物在正、负离子模式下均得到较好的质谱信息, 且在正离子模式下, 电喷雾质谱分析的灵敏度更高. 同时获得了其质谱裂解规律, 为白芍中其它化合物的分析鉴定提供了有效的质谱方法.     

纳升电喷雾串联质谱分析修饰多肽及未知多肽的结构

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Data Interpretation in Mass Spectrometry

An algorithm was proposed for interpreting mass spectra. It allows sufficiently reliable determination of some individual components and improves the resolution of the procedure. The algorithm can be recommended for use with commercial instruments based on time-of-flight mass analyzers and mirror electro energy analyzers and is characterized by low resolution (today no more than 500, e.g. LAMMA-500 and LAMMA-1000).__________Translated from Zhurnal Analiticheskoi Khimii, Vol. 60, No. 8, 2005, pp. 790–793.Original Russian Text Copyright © 2005 by Burlaka, Maiboroda, Startseva.     

Deciphering In-vivo Cross-linking Mass Spectrometry Data for Dynamic Protein Structure Analysis

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Tandem Mass Spectrometry of Small,Multiply Charged Oligonucleotides

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Electrospray Ionization Tandem Mass Spectrometry of Ammonium Cationized Polyethers

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