Guo C, Guo X, Zhao L, Chen D, Wang J, Sun J. Optimization of carbamylation conditions and study on the effects on the product ions of carbamylation and dual modification of the peptide by Q-TOF MS.
EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2018;
24:384-396. [PMID:
30041545 DOI:
10.1177/1469066718788665]
[Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Modified peptides fragmented by collision-induced dissociation can offer additional sequence information, which is beneficial for the de novo sequencing of peptides. Here, the model peptide VQGESNDLK was carbamylated. The optimal conditions were as follows: temperature of 90℃, pH of 7, and the time of 60 min. Then, we studied the b- and y-series ions of the native, carbamylated, and dual-modified peptides. The results were as follows. The short carbamylated peptides (≤10 amino acid residues) produced more b-series ions (including b1 ion). The long carbamylated peptides (>10 amino acid residues) produced additional b1 ion but fewer y-series ions (especially in the high-mass region). The short dual-modified peptides produced more b-series ions (including b1 ion) and more y-series ions, and their peptide sequence coverage was almost 100%. The long dual-modified peptides produce b1 ion and more y-series ions, and their peptide sequence coverage was nearly above 90%. Therefore, both carbamylation and the dual modification method could be used to identify the N-terminal amino acid, and the dual modification method was also excellent for the de novo sequencing of the tryptic peptides.
Collapse