6GAM:
reference: Mechanistic Exploitation of a Self-Repairing, Blocked Proton Transfer Pathway in an O2-Tolerant [NiFe]-Hydrogenase., Evans RM, Ash PA, Beaton SE, Brooke EJ, Vincent KA, Carr SB, Armstrong FA, J Am Chem Soc. 2018 Aug 15;140(32):10208-10220. doi: 10.1021/jacs.8b04798. Epub, 2018 Aug 2. PMID: 30070475

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