Isolation and sequence analysis of peptides from the skin secretion of the Middle East tree frog Hyla savignyi
peer-reviewed · Analytical and Bioanalytical Chemistry · 2010
| Date | 2010-12-01 |
| Type | peer-reviewed |
| Venue | Analytical and Bioanalytical Chemistry |
| Publisher | Springer Science and Business Media LLC |
| Contribution | downstream-application |
| DOI | 10.1007/s00216-010-4131-8 |
| Citations (OpenAlex) | 5 |
Abstract
Novel peptides were identified in the skin secretion of the tree frog Hyla savignyi. Skin secretions were collected by mild electrical stimulation. Peptides were separated by reversed-phase high-performance liquid chromatography. Mass spectra were acquired by electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS), and fragment ion spectra were obtained after collision-induced dissociation and electron capture dissociation. Peptides were analyzed by manual de novo sequencing and composition-based sequencing (CBS). Sequence analyses of three so far undescribed, structurally unrelated peptides are presented in this paper, having the sequences DDSEEEEVE-OH, P*EEVEEERJK-OH, and GJJDPJTGJVGGJJ-NH(2). The glutamate-rich sequences are assumed to be acidic spacer peptides of the prepropeptide. One of these peptides contains the modified amino acid hydroxyproline, as identified and localized by high-accuracy FTICR-MS. Combination of CBS and of experience-based manual sequence analysis as complementary and database-independent sequencing strategies resulted in peptide identification with high reliability.
Methods and tools
- Hyla savignyi spacer peptides: Three previously undescribed peptides, including a hydroxyproline-containing one, from the Middle East tree frog skin secretion were sequenced by manual de novo and composition-based sequencing.
Methods it uses
- Composition-based sequencing: Two-step database-free strategy enabled by FT-ICR mass accuracy: determine the peptide’s amino acid COMPOSITION first, then score only the permutations that composition allows, which is a far smaller search space than conventional de novo sequencing explores.
- Manual MS/MS de novo interpretation: Protocol for manual de novo peptide sequencing from MS/MS spectra.