2IB5:
reference: Structural Characterization of a Blue Chromoprotein and Its Yellow Mutant from the Sea Anemone Cnidopus Japonicus., Chan MC, Karasawa S, Mizuno H, Bosanac I, Ho D, Prive GG, Miyawaki A, Ikura M, J Biol Chem. 2006 Dec 8;281(49):37813-37819. Epub 2006 Oct 6. PMID: 17028187

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