2BKM:
reference: Crystal structure and ligand binding properties of the truncated hemoglobin from Geobacillus stearothermophilus., Ilari A, Kjelgaard P, von Wachenfeldt C, Catacchio B, Chiancone E, Boffi A, Arch Biochem Biophys. 2007 Jan 1;457(1):85-94. Epub 2006 Oct 30. PMID: 17126283

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