5YCE:
reference: Tracing whale myoglobin evolution by resurrecting ancient proteins., Isogai Y, Imamura H, Nakae S, Sumi T, Takahashi KI, Nakagawa T, Tsuneshige A, Shirai T, Sci Rep. 2018 Nov 15;8(1):16883. doi: 10.1038/s41598-018-34984-6. PMID: 30442991

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