4KJT:
reference: Influence of heme environment structure on dioxygen affinity for the dual function Amphitrite ornata hemoglobin/dehaloperoxidase. Insights into the evolutional structure-function adaptations., Sun S, Sono M, Wang C, Du J, Lebioda L, Dawson JH, Arch Biochem Biophys. 2014 Mar 1;545:108-15. doi: 10.1016/j.abb.2014.01.010. Epub, 2014 Jan 16. PMID: 24440609

This OCA Structure page
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