2HYS:
reference: Assignment of the ferriheme resonances of the low-spin complexes of nitrophorins 1 and 4 by (1)H and (13)C NMR spectroscopy: comparison to structural data obtained from X-ray crystallography., Shokhireva TKh, Weichsel A, Smith KM, Berry RE, Shokhirev NV, Balfour CA, Zhang H, Montfort WR, Walker FA, Inorg Chem. 2007 Mar 19;46(6):2041-56. Epub 2007 Feb 10. PMID: 17290983

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