3ZE6:
reference: The three-dimensional structure of [NiFeSe] hydrogenase from Desulfovibrio vulgaris Hildenborough: a hydrogenase without a bridging ligand in the active site in its oxidised, "as-isolated" state., Marques MC, Coelho R, De Lacey AL, Pereira IA, Matias PM, J Mol Biol. 2010 Mar 5;396(4):893-907. Epub 2009 Dec 21. PMID: 20026074

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