4N8T:
reference: Crystallographic characterization of the nitric oxide derivative of R-state human hemoglobin., Yi J, Soares AS, Richter-Addo GB, Nitric Oxide. 2014 May 30;39:46-50. doi: 10.1016/j.niox.2014.04.001. Epub 2014, Apr 22. PMID: 24769418

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