6EFE:
reference: Definition of the R-superfamily of conotoxins: Structural convergence of helix-loop-helix peptidic scaffolds., Moller C, Dovell S, Melaun C, Mari F, Peptides. 2018 Sep;107:75-82. doi: 10.1016/j.peptides.2018.06.002. Epub 2018 Jul , 21. PMID: 30040981

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