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Global Identification of Protein Post-translational Modifications in a Single-Pass Database Search.

ABSTRACT: Bottom-up proteomics database search algorithms used for peptide identification cannot comprehensively identify post-translational modifications (PTMs) in a single-pass because of high false discovery rates (FDRs). A new approach to database searching enables global PTM (G-PTM) identification by exclusively looking for curated PTMs, thereby avoiding the FDR penalty experienced during conventional variable modification searches. We identified over 2200 unique, high-confidence modified peptides comprising 26 different PTM types in a single-pass database search.

SUBMITTER: Shortreed MR

PROVIDER: S-EPMC4642219 | biostudies-literature | 2015 Nov

REPOSITORIES: biostudies-literature

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Global Identification of Protein Post-translational Modifications in a Single-Pass Database Search.

Shortreed Michael R MR Wenger Craig D CD Frey Brian L BL Sheynkman Gloria M GM Scalf Mark M Keller Mark P MP Attie Alan D AD Smith Lloyd M LM

Journal of proteome research 20150929 11

Bottom-up proteomics database search algorithms used for peptide identification cannot comprehensively identify post-translational modifications (PTMs) in a single-pass because of high false discovery rates (FDRs). A new approach to database searching enables global PTM (G-PTM) identification by exclusively looking for curated PTMs, thereby avoiding the FDR penalty experienced during conventional variable modification searches. We identified over 2200 unique, high-confidence modified peptides co ...[more]

PMID: 26418581

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