3R0G:
reference: Structural heterogeneity and ligand gating in ferric methanosarcina acetivorans protoglobin mutants., Pesce A, Tilleman L, Dewilde S, Ascenzi P, Coletta M, Ciaccio C, Bruno S, Moens L, Bolognesi M, Nardini M, IUBMB Life. 2011 May;63(5):287-94. doi: 10.1002/iub.484. PMID: 21618401

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