4F4O:
reference: Structure of the haptoglobin-haemoglobin complex., Andersen CB, Torvund-Jensen M, Nielsen MJ, de Oliveira CL, Hersleth HP, Andersen NH, Pedersen JS, Andersen GR, Moestrup SK, Nature. 2012 Sep 20;489(7416):456-9. doi: 10.1038/nature11369. Epub 2012 Aug 26. PMID: 22922649

This OCA Structure page
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