Fundamental Sessions
Day 1, June 10（Wed.） 14:44-15:02 Room D (5F 511+512)
- 1D-O1-1444
Development of a 7-Methoxycoumarin Derivatization-aided De Novo Peptide Sequencing using LC-MS/MS for Non-Targeted Peptidomics
(1Kyushu Univ., 2Kyushu Univ.)
oMitsuru Tanaka1,2, Hui Luan1, Yumiko Toyama2, Fumiya Honda1, Ryotaro Asai1, Risa Katagihara1, Yizhi Xiao1, Saya Nakamura1, Toshiro Matsui1,2
De novo peptide sequencing by LC–MS/MS is a powerful approach for non-targeted peptidomics but remains limited by insufficient fragment ions for complete sequencing. Here, we developed an N-succinimidyl 7-methoxycoumarin-3-carboxylate (Met-Cou) -derivatization–based LC–MS/MS workflow to enhance sequence-informative fragmentation. Among a variety of amine-derivatizing agents, Met-Cou produced the most effective fragment ion patterns. This Met-Cou derivatization enabled de novo sequencing of peptides with at least 10 amino acid residues. In the analysis of an 86 dipeptide mixture, all peptides were successfully sequenced, whereas the non-derivatized analysis was insufficient. The method was further validated using casein hydrolysate, resulting in the identification of 328 peptides, all derived from the casein sequence. These results demonstrate that Met-Cou–assisted LC–MS/MS provides a promising strategy for de novo sequencing in non-targeted peptidomics. The method shows strong potential for comprehensive low-molecular-weight peptidomics and for the discovery of bioactive and biomarker peptides in food and biological samples.