1GBV:
reference: Cysteines beta93 and beta112 as probes of conformational and functional events at the human hemoglobin subunit interfaces., Vasquez GB, Karavitis M, Ji X, Pechik I, Brinigar WS, Gilliland GL, Fronticelli C, Biophys J 1999 Jan;76(1 Pt 1):88-97. PMID: 9876125

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