HiLight-PTM

HiLight-PTM compares pairs of tandem mass spectrometry (MS/MS) spectra to match peptides carrying heavy and light isotopically labelled post-translational modifications (PTMs), improving peptide annotation and supporting de novo sequencing.

Key Features:

• Spectra Comparison: Performs direct comparison of tandem mass spectrometry (MS/MS) spectra to identify matching peaks between peptide pairs.
• Mass Shift Identification: Identifies peaks that differ by the expected mass shift between heavy and light isotopic PTMs and reports the corresponding m/z values.
• High Confidence Matches: Predicts masses of complementary ions from exact-match peaks to highlight high-confidence spectral matches between paired spectra.
• De Novo Sequencing Support: Produces downloadable lists of identified peaks to support de novo peptide sequencing.

Scientific Applications:

• Proteomics of isotopically labelled PTMs: Assists studies using isotopic labelling to identify and compare post-translational modifications across samples.
• Peptide annotation and PTM confirmation: Improves peptide annotation by identifying matching and mass-shifted peaks and confirming PTMs via complementary ion prediction.
• De novo sequencing: Supplies matched-peak information and peak lists to aid de novo sequencing when database searches fail to assign labelled PTMs.

Methodology:

Analyzes pairs of MS/MS spectra that differ by isotopic labelling, identifies matching peaks and peaks differing by the heavy–light mass shift, and predicts complementary ion masses from exact-match peaks.