Probably participates in a plant defense mechanism. Has low hemolytic activity. The presence of a 'disulfide through disulfide knot' structurally defines this protein as a knottin. Violacin-A is not a cyclic peptide. The presence of a premature stop codon inhibits the translation of a key Asn residue that is thought to be required for cyclization. Belongs to the cyclotide family. Moebius subfamily.