2I28:
reference: NMR structure determination of alpha-conotoxin BuIA, a novel neuronal nicotinic acetylcholine receptor antagonist with an unusual 4/4 disulfide scaffold., Chi SW, Kim DH, Olivera BM, McIntosh JM, Han KH, Biochem Biophys Res Commun. 2006 Nov 3;349(4):1228-34. Epub 2006 Sep 7. PMID: 16979596

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