4OS6:
reference: Dithiol amino acids can structurally shape and enhance the ligand-binding properties of polypeptides., Chen S, Gopalakrishnan R, Schaer T, Marger F, Hovius R, Bertrand D, Pojer F, Heinis C, Nat Chem. 2014 Nov;6(11):1009-16. doi: 10.1038/nchem.2043. Epub 2014 Aug 31. PMID: 25343607

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