4NPP:
reference: Crystal structures of a pentameric ligand-gated ion channel provide a mechanism for activation., Sauguet L, Shahsavar A, Poitevin F, Huon C, Menny A, Nemecz A, Haouz A, Changeux JP, Corringer PJ, Delarue M, Proc Natl Acad Sci U S A. 2014 Jan 21;111(3):966-71. doi:, 10.1073/pnas.1314997111. Epub 2013 Dec 23. PMID: 24367074

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