5LFG:
reference: Fine Sampling of the R-->T Quaternary-Structure Transition of a Tetrameric Hemoglobin., Vitagliano L, Mazzarella L, Merlino A, Vergara A, Chemistry. 2017 Jan 12;23(3):605-613. doi: 10.1002/chem.201603421. Epub 2016 Dec , 7. PMID: 27808442

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