2ZLV:
reference: Water-mediated variability in the structure of relaxed-state haemoglobin., Kaushal PS, Sankaranarayanan R, Vijayan M, Acta Crystallogr Sect F Struct Biol Cryst Commun. 2008 Jun 1;64(Pt, 6):463-9. Epub 2008 May 17. PMID: 18540052

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