1Z99:
reference: Automated NMR structure determination and disulfide bond identification of the myotoxin crotamine from Crotalus durissus terrificus., Fadel V, Bettendorff P, Herrmann T, de Azevedo WF Jr, Oliveira EB, Yamane T, Wuthrich K, Toxicon. 2005 Dec 1;46(7):759-67. Epub 2005 Sep 26. PMID: 16185738

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