Phosphopeptide analysis by positive and negative ion matrix-assisted laser desorption/ionization mass spectrometry
Phosphopeptide analysis by positive and negative ion matrix-assisted laser desorption/ionization mass spectrometry
复制标题
DOI：
10.1002/rcm.417
复制
发表时间：
2001-01-01
影响因子：
2
通讯作者：
Krause, E
中科院分区：
文献类型：
--
作者：
Janek, K;Wenschuh, H;Krause, E
本文介绍了一个简单的程序，可比较的正离子和负离子模式基质辅助激光解吸/电离质谱测量磷酸化肽的检测。基于对磷酸化肽（EAIXAAPFAK，X = pS，pT，pY）及其相应的非磷酸化类似物的研究，发现特征在于在正离子模式下的低电离效率的磷酸肽与其非磷酸化类似物相比在负离子模式下表现出急剧增加的信号强度。该效应被成功地用于鉴定常用的磷蛋白标准品、蛋白激酶A和β-酪蛋白的磷酸化序列，通过使用两种（正和负）离子模式对相应的Lys C和胰蛋白酶底物进行肽质量指纹分析。给定蛋白质消化物的正离子谱和负离子谱的比较（相对强度（[M-H]-）/相对强度（[M + H]+））可用于鉴定存在的任何磷酸肽，然后可将其分离并进一步分析。版权所有（C）2001约翰威利父子有限公司
This article describes a simple procedure for the detection of phosphorylated peptides by comparable positive and negative ion mode matrix-assisted laser desorption/ionization mass spectrometry measurements. Based on studies with phosphorylated peptides (EAIXAAPFAK, X = pS, pT, pY) and their corresponding non-phosphorylated analogs, it was found that phosphopeptides, which are characterized by a low ionization efficiency in the positive ion mode, exhibit drastically increased signal intensities in the negative ion mode compared to their nonphosphorylated analogs. The effect was successfully used to identify phosphorylated sequences of the commonly used phosphoprotein standards, protein kinase A and beta -casein, by peptide mass fingerprint analyses of the corresponding Lys C and trypsin digests using both (positive and negative) ion modes. The comparison of positive and negative ion spectra of a given protein digest (relative intensity([M - H]-)/relative intensity([M + H]+)) can be used to identify any phosphopeptides present which may then be separated and analyzed further. Copyright (C) 2001 John Wiley & Sons, Ltd.