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PubMed · 10870951

Fluorescent modification for peptide sequencing by postsource decay-matrix assisted laser desorption/ionization-mass spectrometry.

M Nakagawa·T Yamagaki·H Nakanishi
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Abstract

The sequential analysis of a peptide of CDYEGRLI, relating to the nucleic proteins in influenza virus, was performed by the postsource decay (PSD) fragmentation method using matrix assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS). The sequence of the peptide was difficult to analyze by MALDI-MS since the PSD fragment ions of the peptide were almost never observed and were not amenable to complete sequence interpretation. The peptide was modified by 4(5)-(iodoacetamide) fluorescent reagent to improve the sensitivity of the MALDI-PSD fragment spectrum. In the spectrum of the fluorescent modified peptide, almost all sequential b-series fragment ions were observed clearly, which was sufficient for complete sequence interpretation. The results indicate the advantage of fluorescent modification for the total sequencing of the peptides by MALDI-MS.

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FluoresceinsFluorescenceOrthomyxoviridaePeptidesSequence Analysis, ProteinSpectrometry, Mass, Matrix-Assisted Laser Desorption-IonizationViral ProteinsJournal Article

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M Nakagawa, T Yamagaki, H Nakanishi. 2000. Fluorescent modification for peptide sequencing by postsource decay-matrix assisted laser desorption/ionization-mass spectrometry.. https://doi.org/10.1002/(sici)1522-2683(20000501)21%3A9%3C1651%3A%3Aaid-elps1651%3E3.0.co%3B2-l

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