1YMA:
reference: Structural characterization of heme ligation in the His64-->Tyr variant of myoglobin., Maurus R, Bogumil R, Luo Y, Tang HL, Smith M, Mauk AG, Brayer GD, J Biol Chem 1994 Apr 29;269(17):12606-10. PMID: 8175669

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