4Z9K:
reference: Structural analysis of nested neutralizing and non-neutralizing B cell epitopes on ricin toxin's enzymatic subunit., Rudolph MJ, Vance DJ, Cassidy MS, Rong Y, Shoemaker CB, Mantis NJ, Proteins. 2016 Aug;84(8):1162-72. doi: 10.1002/prot.25062. Epub 2016 Jun 15. PMID: 27159829

This OCA Structure page
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