4ALO:
reference: Structural characterization of recombinant crustacyanin subunits from the lobster Homarus americanus., Ferrari M, Folli C, Pincolini E, McClintock TS, Rossle M, Berni R, Cianci M, Acta Crystallogr Sect F Struct Biol Cryst Commun. 2012 Aug 1;68(Pt 8):846-53., Epub 2012 Jul 26. PMID: 22869108

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