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Evidence for multiple differing cation binding sites on hemoglobin A and S.

G Amiconi·L Civalleri·S G Condò·F Ascoli·R Santucci·E Antonini
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Abstract

Some divalent cations (at 10(-3)M concentration) have been shown to act as oxygen-linked ligands. The effect of Ca++ (only on hemoglobin S) and Zn++ (on normal hemoglobin and hemoglobin S) can be traced to a preferential binding of these cations to the oxy- conformation of the proteins; the reverse is true for Ni++, since its presence reduces the oxygen affinity of both hemoglobins. The results suggest: i) the existence of at least two different cation binding sites on hemoglobin; ii) the replacement of glutamic acid by valine in hemoglobins S introduces sufficient structural modification to form a new cation binding site.

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Binding SitesCations, DivalentCircular DichroismGlutamatesGlutamic AcidHemoglobin AHemoglobin, SickleHumansOxygen ConsumptionProtein ConformationValineJournal Article

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BibTeXRIS

G Amiconi, L Civalleri, S G Condò, F Ascoli, R Santucci, E Antonini. 1981. Evidence for multiple differing cation binding sites on hemoglobin A and S.. https://doi.org/10.3109/03630268108997547

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