DIA-MS2pep

DIA-MS2pep performs library-free peptide identification directly from data-independent acquisition (DIA) MS/MS spectra to enable comprehensive detection of peptides and their modified forms.

Key Features:

• Library-free identification: Operates without spectral libraries to enable identification of peptides beyond those cataloged in existing databases.
• Data-driven MS/MS spectrum demultiplexing: Demultiplexes MS/MS spectra directly from fragment ions without requiring precursor information to handle highly multiplexed DIA spectra.
• Large precursor mass tolerance database search: Uses a broad precursor mass tolerance during database searches to identify peptides and modified peptide forms.
• DIA-derived spectral library construction: Builds spectral libraries directly from DIA data to support downstream quantitative analyses.
• Validated performance: Comparative studies show improved accuracy and sensitivity in peptide identification versus conventional library-free tools and improved quantitative accuracy and reproducibility relative to spectral libraries derived from data-dependent acquisition (DDA).

Scientific Applications:

• Cellular proteomics: Enables detailed proteomic analysis of cellular samples such as HeLa cell lysates.
• Phosphoproteomics: Facilitates identification of post-translational modifications including phosphorylation.
• Clinical and biological fluids analysis: Applicable to plasma samples for applications such as biomarker discovery and disease characterization.
• Quantitative proteomics: Supports generation of DIA-derived spectral libraries that improve quantitative accuracy and reproducibility.

Methodology:

DIA-MS2pep applies a data-driven algorithm to demultiplex MS/MS spectra from fragment ions without relying on precursor information and performs database searches using large precursor mass tolerances.