page_title: Cyclotide
section_title: History
hierarchical_section_title: Cyclotide / History
caption_attribution_description: English: Kalata, 2002 Sculpture based on the structure of the protein kalata B1 Painted steel, length 3' (90 cm)
context_page_description: Cyclotides are small disulfide rich peptides isolated from plants. Typically containing 28-37 amino acids, they are characterized by their head-to-tail cyclised peptide backbone and the interlocking arrangement of their three disulfide bonds. These combined features have been termed the cyclic cystine knot motif. To date, over 100 cyclotides have been isolated and characterized from species of the families Rubiaceae, Violaceae, and Cucurbitaceae. Cyclotides have also been identified in agriculturally important families such as the Fabaceae and Poaceae.
context_section_description: During a Red Cross relief mission in the Democratic Republic of Congo during the 1960s, a Norwegian doctor, Lorents Gran, noted that during labor African women used a medicinal tea made from the leaves of the plant Oldenlandia affinis to induce labor and facilitate childbirth.  The active ingredient was later determined to be a peptide, named kalata B1, after the traditional name for the native medicine, kalata-kalata.  Although in vivo studies in rats confirmed the uterotonic activity of the purified peptide, it was another 20 years before the cyclic cystine knot motif and structure of the purified peptide were elucidated.
caption: Kalata (2002) by Julian Voss-Andreae. The pictured sculpture is based on the atomic coordinates of kalata B1.[27]
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