Transition of hemoglobin between two tertiary conformations: Determination of equilibrium and thermodynamic parameters from the reaction of 5,5′-dithiobis(2-nitrobenzoate) with the CysF9[93]β sulfhydryl group

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The equilibrium constant of the reaction of 5,5′-dithiobis(2-nitrobenzoate) with the CysF9[93]β sulfhydryl group of hemoglobin decreases by 2 to 3 orders of magnitude between pH 5.6 and 9. The reaction is coupled to the ionizations of two groups on the protein. At 25 °C one group has a pKa of 5.31±0.2 when hemoglobin is in its (tertiary) r conformation, typified by the thiolate anion...

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KO Okonjo, AT Adediji, AA Fodeke, O. Adeboye & CV Ezeh

Okonjo Kehinde » Born 1942. Educated King's College, Lagos (1957-63). BSc, PhD (University of Ibadan). Retired Professor of Chemistry, University of Ibadan. Currently Professor of Chemistry, Covenant University. Current research interests: Kinetics and thermodynamics of reactions of reaction of Ellman's reagent with hemoglobin sulphydryl groups. Publications in such high impact journals as the Journal of... view full profile

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