6F0O:
reference: High resolution crystal structures of Clostridium botulinum neurotoxin A3 and A4 binding domains., Davies JR, Rees J, Liu SM, Acharya KR, J Struct Biol. 2017 Dec 26. pii: S1047-8477(17)30233-2. doi:, 10.1016/j.jsb.2017.12.010. PMID: 29288126

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