ID   VITA_VIOAR              Reviewed;          30 AA.
AC   P83840;
DT   10-MAY-2004, integrated into UniProtKB/Swiss-Prot.
DT   10-MAY-2004, sequence version 1.
DT   25-MAY-2022, entry version 45.
DE   RecName: Full=Vitri peptide A;
OS   Viola arvensis (European field pansy) (Field violet).
OC   Eukaryota; Viridiplantae; Streptophyta; Embryophyta; Tracheophyta;
OC   Spermatophyta; Magnoliopsida; eudicotyledons; Gunneridae; Pentapetalae;
OC   rosids; fabids; Malpighiales; Violaceae; Viola.
OX   NCBI_TaxID=97415;
RN   [1] {ECO:0000305}
RP   PROTEIN SEQUENCE, FUNCTION, AND MASS SPECTROMETRY.
RX   PubMed=14987049; DOI=10.1021/np030101l;
RA   Svangard E., Goransson U., Hocaoglu Z., Gullbo J., Larsson R., Claeson P.,
RA   Bohlin L.;
RT   "Cytotoxic cyclotides from Viola tricolor.";
RL   J. Nat. Prod. 67:144-147(2004).
CC   -!- FUNCTION: Probably participates in a plant defense mechanism. Has
CC       strong cytotoxic activity against human lymphoma U-937 GTB and human
CC       myeloma RPMI-8226/s cell lines. {ECO:0000255|PROSITE-ProRule:PRU00395,
CC       ECO:0000269|PubMed:14987049, ECO:0000305}.
CC   -!- DOMAIN: The presence of a 'disulfide through disulfide knot'
CC       structurally defines this protein as a knottin.
CC       {ECO:0000250|UniProtKB:P56871}.
CC   -!- PTM: This is a cyclic peptide. {ECO:0000255|PROSITE-ProRule:PRU00395,
CC       ECO:0000269|PubMed:14987049}.
CC   -!- MASS SPECTROMETRY: Mass=3153; Method=Electrospray;
CC       Evidence={ECO:0000269|PubMed:14987049};
CC   -!- SIMILARITY: Belongs to the cyclotide family. Bracelet subfamily.
CC       {ECO:0000255|PROSITE-ProRule:PRU00395}.
CC   -!- CAUTION: This peptide is cyclic. The start position was chosen by
CC       similarity to OAK1 (kalata-B1) for which the DNA sequence is known.
CC       {ECO:0000305}.
CC   ---------------------------------------------------------------------------
CC   Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms
CC   Distributed under the Creative Commons Attribution (CC BY 4.0) License
CC   ---------------------------------------------------------------------------
DR   AlphaFoldDB; P83840; -.
DR   SMR; P83840; -.
DR   GO; GO:0006952; P:defense response; IDA:UniProtKB.
DR   InterPro; IPR005535; Cyclotide.
DR   InterPro; IPR012323; Cyclotide_bracelet_CS.
DR   InterPro; IPR036146; Cyclotide_sf.
DR   Pfam; PF03784; Cyclotide; 1.
DR   PIRSF; PIRSF037891; Cycloviolacin; 1.
DR   SUPFAM; SSF57038; SSF57038; 1.
DR   PROSITE; PS51052; CYCLOTIDE; 1.
DR   PROSITE; PS60008; CYCLOTIDE_BRACELET; 1.
PE   1: Evidence at protein level;
KW   Direct protein sequencing; Disulfide bond; Knottin; Plant defense.
FT   PEPTIDE         1..30
FT                   /note="Vitri peptide A"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00395,
FT                   ECO:0000269|PubMed:14987049"
FT                   /id="PRO_0000043633"
FT   DISULFID        4..20
FT                   /evidence="ECO:0000250|UniProtKB:P56871,
FT                   ECO:0000255|PROSITE-ProRule:PRU00395"
FT   DISULFID        8..22
FT                   /evidence="ECO:0000250|UniProtKB:P56871,
FT                   ECO:0000255|PROSITE-ProRule:PRU00395"
FT   DISULFID        13..27
FT                   /evidence="ECO:0000250|UniProtKB:P56871,
FT                   ECO:0000255|PROSITE-ProRule:PRU00395"
FT   CROSSLNK        1..30
FT                   /note="Cyclopeptide (Gly-Asn)"
FT                   /evidence="ECO:0000269|PubMed:14987049"
SQ   SEQUENCE   30 AA;  3179 MW;  B9819A52EACD5FE3 CRC64;
     GIPCGESCVW IPCITSAIGC SCKSKVCYRN