1EA5:
reference: X-ray structures of Torpedo californica acetylcholinesterase complexed with (+)-huperzine A and (-)-huperzine B: structural evidence for an active site rearrangement., Dvir H, Jiang HL, Wong DM, Harel M, Chetrit M, He XC, Jin GY, Yu GL, Tang XC, Silman I, Bai DL, Sussman JL, Biochemistry. 2002 Sep 3;41(35):10810-8. PMID: 12196020

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