{"title":"Cysteine-free cone snail venom peptides: Classification of precursor proteins and identification of mature peptides","authors":"Marimuthu Vijayasarathy, Sanjeev Kumar, Rajdeep Das, Padmanabhan Balaram","doi":"10.1002/psc.3554","DOIUrl":null,"url":null,"abstract":"<p>The cysteine-free acyclic peptides present in marine cone snail venom have been much less investigated than their disulfide bonded counterparts. Precursor protein sequences derived from transcriptomic data, together with mass spectrometric fragmentation patterns for peptides present in venom duct tissue extracts, permit the identification of mature peptides. Twelve distinct gene superfamiles have been identified with precursor lengths between 64 and 158 residues. In the case of <i>Conus monile</i>, three distinct mature peptides have been identified, arising from two distinct protein precursors. Mature acyclic peptides are often post-translationally modified, with C-terminus amidation, a feature characteristic of neuropeptides. In the present study, 20 acyclic peptides from <i>Conus monile</i> and <i>Conus betulinus</i> were identified. The common modifications of C-terminus amidation, gamma carboxylation of glutamic acid (E to ϒ), N-terminus conversion of Gln (Q) to a pyroglutamyl residue (Z), and hydroxylation of Pro (P) to Hyp (O) are observed in one or more peptides identified in this study. Proteolytic trimming of sequences by cleavage at the C-terminus of Asn (N) residues is established. The presence of an asparagine endopeptidase is strengthened by the identification of legumain-like sequences in the transcriptome assemblies from diverse <i>Conus</i> species. Such sequences may be expected to have a cleavage specificity at Asn-Xxx peptide bonds.</p>","PeriodicalId":16946,"journal":{"name":"Journal of Peptide Science","volume":null,"pages":null},"PeriodicalIF":1.8000,"publicationDate":"2023-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Peptide Science","FirstCategoryId":"99","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1002/psc.3554","RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"BIOCHEMISTRY & MOLECULAR BIOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
The cysteine-free acyclic peptides present in marine cone snail venom have been much less investigated than their disulfide bonded counterparts. Precursor protein sequences derived from transcriptomic data, together with mass spectrometric fragmentation patterns for peptides present in venom duct tissue extracts, permit the identification of mature peptides. Twelve distinct gene superfamiles have been identified with precursor lengths between 64 and 158 residues. In the case of Conus monile, three distinct mature peptides have been identified, arising from two distinct protein precursors. Mature acyclic peptides are often post-translationally modified, with C-terminus amidation, a feature characteristic of neuropeptides. In the present study, 20 acyclic peptides from Conus monile and Conus betulinus were identified. The common modifications of C-terminus amidation, gamma carboxylation of glutamic acid (E to ϒ), N-terminus conversion of Gln (Q) to a pyroglutamyl residue (Z), and hydroxylation of Pro (P) to Hyp (O) are observed in one or more peptides identified in this study. Proteolytic trimming of sequences by cleavage at the C-terminus of Asn (N) residues is established. The presence of an asparagine endopeptidase is strengthened by the identification of legumain-like sequences in the transcriptome assemblies from diverse Conus species. Such sequences may be expected to have a cleavage specificity at Asn-Xxx peptide bonds.
期刊介绍:
The official Journal of the European Peptide Society EPS
The Journal of Peptide Science is a cooperative venture of John Wiley & Sons, Ltd and the European Peptide Society, undertaken for the advancement of international peptide science by the publication of original research results and reviews. The Journal of Peptide Science publishes three types of articles: Research Articles, Rapid Communications and Reviews.
The scope of the Journal embraces the whole range of peptide chemistry and biology: the isolation, characterisation, synthesis properties (chemical, physical, conformational, pharmacological, endocrine and immunological) and applications of natural peptides; studies of their analogues, including peptidomimetics; peptide antibiotics and other peptide-derived complex natural products; peptide and peptide-related drug design and development; peptide materials and nanomaterials science; combinatorial peptide research; the chemical synthesis of proteins; and methodological advances in all these areas. The spectrum of interests is well illustrated by the published proceedings of the regular international Symposia of the European, American, Japanese, Australian, Chinese and Indian Peptide Societies.