Distinguishing N-Terminal Methylation from Near-isobaric Modifications by Statistical Analysis of Mass Error Distributions of Fragment Ions
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ABSTRACT:
INSTRUMENT(S): Q Exactive
ORGANISM(S): Homo Sapiens (ncbitaxon:9606)
SUBMITTER: 
Cheolju lee
PROVIDER: MSV000096415 | MassIVE | Thu Nov 14 05:38:00 GMT 2024
SECONDARY ACCESSION(S): PXD057893
REPOSITORIES: MassIVE
Publications
Distinguishing <i>N</i>-Terminal Methylation from Near-Isobaric Modifications by Statistical Analysis of Mass Error Distributions of Fragment Ions.
Lee Hankyul H Ju Shinyeong S Lee Seonjeong S Lee So Ha SH Kim Sang-Yoon SY Park Narae N Hwang Cheol-Sang CS Park Kang-Sik KS Lee Cheolju C
Journal of proteome research 20250730 9
α-<i>N</i>-Terminal methylation is an understudied post-translational modification involved in protein-protein or protein-DNA interactions. Its global profiling by mass spectrometry is challenging due to low abundance and interference from near-isobaric modifications like Nt-acetylation, even after <i>N</i>-terminome enrichment. To address this problem, we assume that a-, b-, and y-ions will exhibit different mass error distributions in MS2 spectra if falsely assigned to a near-isobaric Nt-modif ...[more]
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