5MOO:
reference: Charges Shift Protonation: Neutron Diffraction Reveals that Aniline and 2-Aminopyridine Become Protonated Upon Binding to Trypsin., Schiebel J, Gaspari R, Sandner A, Ngo K, Gerber HD, Cavalli A, Ostermann A, Heine A, Klebe G, Angew Chem Int Ed Engl. 2017 Apr 18;56(17):4887-4890. doi:, 10.1002/anie.201701038. Epub 2017 Mar 28. PMID: 28371253

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