3HGN:
reference: Combined High-Resolution Neutron and X-ray Analysis of Inhibited Elastase Confirms the Active-Site Oxyanion Hole but Rules against a Low-Barrier Hydrogen Bond., Tamada T, Kinoshita T, Kurihara K, Adachi M, Ohhara T, Imai K, Kuroki R, Tada T, J Am Chem Soc. 2009 Jul 15. PMID: 19603802

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