Dataset Information

Exploring the diversity of cysteine-rich natural product peptides via MS/MS fingerprint ions

ABSTRACT: Stable and commonly bioactive cysteine-rich peptides (CRPs) have are typically discovered via mass shift analysis. However, the accurate assessment of unique CRP species in a given botanical species is often challenged by same mass species, post-translational modifications or modifications derived from sample handling, and incomplete MS2 fragmentation. Mass spectral fingerprint ions can be leveraged to gain additional information about a mass species prior to full sequence characterization and with only poor quality MS2 spectra. Herein we identify sets of mass spectral fingerprint ions characteristic of the CRP cyclotide family, which may indicate a mass belongs to a specific cyclotide subfamily, and “tell-tale” ions that are of importance when discriminating putative cyclotide species, including common oxidation and over-alkylation ions observed experimentally. Cyclotide-containing V. communis material is used as proof-of-principle, where experimental cyclotide fingerprint ions are explored. Fingerprint ions derived from a third type of CRP, the trypsin inhibitors, are assessed in the gourd L. siceraria. Combining mass shift analysis with the identification of prominent MS2 fingerprint ions is then used to identify three novel CRPs. We demonstrate that abundant mass spectral fingerprint ions can be used to quickly discern masses of interest in complex matrices and masses that are already characterized, aiding prioritization of the most promising novel mass species in a natural product sample for characterization.

INSTRUMENT(S): TripleTOF 5600

ORGANISM(S): Viola <eudicots> Lagenaria Siceraria

TISSUE(S): Seed, Leaf

SUBMITTER: Leslie Hicks

LAB HEAD: Leslie M. Hicks

PROVIDER: PXD019501 | Pride | 2020-09-04

REPOSITORIES: Pride

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Dataset's files

Source:

			Action	DRS
	20190820_NCP_SEEDS_LSS_INT_10XDIL.wiff	Wiff
	20190820_NCP_SEEDS_LSS_INT_10XDIL.wiff.scan	Wiff
	20190820_NCP_SEEDS_LSS_RA_10XDIL.wiff	Wiff
	20190820_NCP_SEEDS_LSS_RA_10XDIL.wiff.scan	Wiff
	20190820_NCP_SEEDS_LSS_RA_10XDIL_10uL.wiff	Wiff

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Publications

Exploring the Diversity of Cysteine-Rich Natural Product Peptides via MS/MS Fingerprint Ions.

Parsley Nicole C NC Williams Owen L OL Hicks Leslie M LM

Journal of the American Society for Mass Spectrometry 20200730 9

Natural product extracts present inherently complex matrices in which the identification of novel bioactive peptide species is challenged by low-abundance masses and significant structural and sequence diversity. Additionally, discovery efforts often result in the re-identification of known compounds, where modifications derived in vivo or during sample handling may obscure true sequence identity. Herein, we identify mass spectral (MS2) "fingerprint" ions characteristic of cycl ...[more]

PMID: 32872784

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