2M6H:
reference: Conformational Diversity in Contryphans from Conus Venom: cis-trans Isomerisation and Aromatic/Proline Interactions in the 23-Membered Ring of a 7-Residue Peptide Disulfide Loop., Sonti R, Gowd KH, Rao KN, Ragothama S, Rodriguez A, Perez JJ, Balaram P, Chemistry. 2013 Nov 4;19(45):15175-89. doi: 10.1002/chem.201301722. Epub 2013 Sep, 23. PMID: 24115170

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