4PUN:
reference: Chasing Protons: How Isothermal Titration Calorimetry, Mutagenesis, and pKa Calculations Trace the Locus of Charge in Ligand Binding to a tRNA-Binding Enzyme., Neeb M, Czodrowski P, Heine A, Barandun LJ, Hohn C, Diederich F, Klebe G, J Med Chem. 2014 Jul 10;57(13):5554-65. doi: 10.1021/jm500401x. Epub 2014 Jun 23. PMID: 24955548

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