Probably participates in a plant defense mechanism. Has strong cytotoxic activity against a variety of drug-resistant and drug-sensitive human tumor cell lines, and against primary chronic lymphocytic leukemia and ovarian carcinoma cells. Has weaker cytotoxic activity against normal lymphocytes. Has hemolytic activity. Expressed in leaves, petals, petioles, roots and runners (at protein level). The presence of a 'disulfide through disulfide knot' structurally defines this protein as a knottin. This is a cyclic peptide. Belongs to the cyclotide family. Bracelet subfamily. This peptide is cyclic. The start position was chosen by similarity to OAK1 (kalata-B1) for which the DNA sequence is known.