3WFT:
reference: Co(II)/Co(I) reduction-induced axial histidine-flipping in myoglobin reconstituted with a cobalt tetradehydrocorrin as a methionine synthase model., Hayashi T, Morita Y, Mizohata E, Oohora K, Ohbayashi J, Inoue T, Hisaeda Y, Chem Commun (Camb). 2014 Oct 25;50(83):12560-3. doi: 10.1039/c4cc05448b. PMID: 25197974

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