Absorption Spectra and Reaction with Haptoglobin of Hemoglobin (a-NO, PUnliganded)
نویسنده
چکیده
Human hemoglobin (aNOD), in which a! chains were liganded with nitric oxide and p chains were unliganded, showed a characteristic spectrum in the Soret region. Its absorption was significantly reduced compared with the averaged absorption of IX-NO and p. On the other hand, a complex of (cuNO0) with haptoglobin did not show such a characteristic spectrum. It was concluded, therefore, that there are some subunit interactions in (cYNOP) and that they are lost when (otNO@ is bound to haptoglobin. Reaction of (CXNOP) with haptoglobin was followed spectrophotometrically, and it was found that the rate of reaction of (aNO/?) with haptoglobin was markedly different from that of fully liganded or fully unliganded hemoglobin with haptoglobin. (olNO0) seems to be in a different conformational state from both fully liganded or fully unliganded hemoglobin.
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