分析化学Issue(7)：1010-1016,7.DOI:10.11895/j.issn.0253-3820.130780
串联飞行时间质谱中亚胺离子的断裂特征及其在肽段鉴定中的作用
Fragmentation Characteristics and Utility of Immonium Ions for Peptide Identification by MALDI TOF/TOF Spectrometry
摘要
Abstract
One of significant characteristics of matrix-assisted laser desorption/ionization tandem time of flight mass spectrometry ( MALD-TOF/TOF ) high-energy collision induced dissociation ( CID ) is to produce abundant immonium ( IM ) ions that can offer a wealth of information for peptide composition. However, MALDI-TOF/TOF is generally used for routine protein identification based on database search or de novo sequencing combined with chemical derivation. Consequently, the characteristics of IM ions may not be fully explored and utilized. Here, a total of 239 MS/MS spectra are used to explore the fragmentation features of IM ions with MALDI TOF/TOF spectrometry and their application for peptide identification. IM ion signals can be observed for 14 kinds of amino acids including histidine etc with a positive rate of more than 50%. We have found that the chemical nature of the amino acids and position effects are the two main factors that affect the intensity of fragment ions. In addition, false positive IM ions are mainly derived from Arg, Lys, Leu and Ile residues or mixture peptides. Besides the compositional information, partial sequence information can also be obtained by a comparison of the relative intensity of IM ions. These findings are helpful when performing manual interpretations and could be useful for improving current peptide search algorithms.关键词
亚胺离子/基质辅助激光解吸电离-串联飞行时间质谱/蛋白质鉴定/肽段鉴定Key words
Immonium ion/Matrix-assisted Laser Desorption ionization tandem time-of-flight mass spectrometry/Protein identification/Peptide identification引用本文复制引用
王勇,李水明,何曼文..串联飞行时间质谱中亚胺离子的断裂特征及其在肽段鉴定中的作用[J].分析化学,2014,(7):1010-1016,7.基金项目
本文系国家自然科学基金(Nos.21271131,31070731)资助项目@@@@This work was supported by the National Natural Science Foundation of China (Nos.21271131,31070731) （Nos.21271131,31070731）
