4OUJ:
reference: High-resolution crystal structure of HA33 of botulinum neurotoxin type B progenitor toxin complex., Lee K, Lam KH, Kruel AM, Perry K, Rummel A, Jin R, Biochem Biophys Res Commun. 2014 Apr 4;446(2):568-73. doi:, 10.1016/j.bbrc.2014.03.008. Epub 2014 Mar 12. PMID: 24631690

This OCA Structure page
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