Effects of Electron-Transfer Coupled with Collision-Induced Dissociation (ET/CID) on Doubly Charged Peptides and Phosphopeptides |
| |
Authors: | Chih-Wei Liu Chien-Chen Lai |
| |
Institution: | (1) Institute of Molecular Biology, National Chung Hsing University, No. 250, Kuo-Kuang Road, Taichung, 402, Taiwan;(2) Graduate Institute of Chinese Medical Science, China Medical University, Taichung, Taiwan |
| |
Abstract: | Electron-transfer dissociation (ETD) is a useful peptide fragmentation technique that can be applied to investigate post-translational
modifications (PTMs), the sequencing of highly hydrophilic peptides, and the identification of large peptides and even intact
proteins. In contrast to traditional fragmentation methods, such as collision-induced dissociation (CID), ETD produces c-
and z·-type product ions by randomly cleaving the N–Cα bonds. The disappointing fragmentation efficiency of ETD for doubly charged
peptides and phosphopeptide ions has been improved by ETcaD (supplemental activation). However, the ETD data derived from
most database search algorithms yield low confidence scores due to the presence of unreacted precursors and charge-reduced
ions within MS/MS spectra. In this work, we demonstrate that eight out of ten standard doubly charged peptides and phosphopeptides
can be effortlessly identified by electron-transfer coupled with collision-induced dissociation (ET/CID) using the SEQUEST
algorithm without further spectral processing. ET/CID was performed with the further dissociation of the charge-reduced ions
isolated from ETD ion/ion reactions. ET/CID had high fragmentation efficiency, which elevated the confidence scores of doubly
charged peptide and phosphospeptide sequencing. ET/CID was found to be an effective fragmentation strategy in “bottom-up”
proteomic analysis. |
| |
Keywords: | |
本文献已被 PubMed SpringerLink 等数据库收录! |
|