Free Radical Initiated Peptide Sequencing for Direct Site Localization of Sulfation and Phosphorylation with Negative Ion Mode Mass Spectrometry.

ABSTRACT: Tandem mass spectrometry (MS/MS) is the primary method for discovering, identifying, and localizing post-translational modifications (PTMs) in proteins. However, conventional positive ion mode collision induced dissociation (CID)-based MS/MS often fails to yield site-specific information for labile and acidic modifications due to low ionization efficiency in positive ion mode and/or preferential PTM loss. While a number of alternative methods have been developed to address this issue, most require specialized instrumentation or indirect detection. In this work, we present an amine-reactive TEMPO-based free radical initiated peptide sequencing (FRIPS) approach for negative ion mode analysis of phosphorylated and sulfated peptides. FRIPS-based fragmentation generates sequence informative ion

SUBMITTER: Borotto NB 

PROVIDER: S-EPMC6235672 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature