2E4M:
reference: A Novel Subunit Structure of Clostridium botulinum Serotype D Toxin Complex with Three Extended Arms., Hasegawa K, Watanabe T, Suzuki T, Yamano A, Oikawa T, Sato Y, Kouguchi H, Yoneyama T, Niwa K, Ikeda T, Ohyama T, J Biol Chem. 2007 Aug 24;282(34):24777-24783. Epub 2007 Jun 20. PMID: 17581814

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