3FFZ:
reference: Domain organization in Clostridium botulinum neurotoxin type E is unique: its implication in faster translocation., Kumaran D, Eswaramoorthy S, Furey W, Navaza J, Sax M, Swaminathan S, J Mol Biol. 2009 Feb 13;386(1):233-45. Epub 2008 Dec 24. PMID: 19118561

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