MS approaches to select peptides with post-translational modifications from amphibian defense secretions prior to full sequence elucidation

Publication date: December 2014 Source:EuPA Open Proteomics, Volume 5 Author(s): Martijn Pinkse , Geisa Evaristo , Mervin Pieterse , Yuanjie Yu , Peter Verhaert Peptide families are characterized by structural motifs, which often comprise specific post-translational modifications (PTMs) required for biological activity. In conventional bioactivity-based peptidomics studies natural peptide mixtures are chromatographically separated and the bioactive fractions purified to homogeneity, prior to structural characterization. In this paper we illustrate the reverse methodology, in which the primary structures of peptides with presumed bioactivity are first determined before investigating functions/bioactivities. We exemplify mass spectrometry (MS)-based strategies (employing, in particular, high resolution MS) to specifically select peptides – from complex mixtures such as frog defensive secretions – by virtue of the occurrence of particular PTMs, including amidation, disulfide-bonding, l- to d-amino acid isomerization, tyrosine-sulfation, proline-hydroxylation, and aminoterminal pyroglutamate formation. Graphical abstract

Source: EuPA Open Proteomics - December 18, 2014 Category: Bioinformatics Source Type: research