Resolvability of free energy changes for oxygen binding and subunit association by human hemoglobin
نویسندگان
چکیده
منابع مشابه
Calorimetric studies of oxygen and carbon monoxide binding to human hemoglobin. Sequential binding heats for oxygen.
Two high precision techniques, titration microcalorimetry and thin-layer optical binding measurements, have made possible the evaluation of enthalpy changes for the overall oxygenation reactions for human hemoglobin (HbAo). Although the heat of adding three oxygen molecules could not be evaluated due to the indeterminate contribution of this species to the oxygen binding curve of the protein (G...
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The role of chloride in the stabilization of the deoxy conformation of hemoglobin (Hb), the low oxygen affinity state, has been studied in order to identify the nature of this binding. Previous studies have shown that arginines 141alpha could be involved in the binding of this ion to the protein. Thus, des-Arg Hb, human hemoglobin modified by removal of the alpha-chain C-terminal residue Arg141...
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Hemoglobin is a tetrameric oxygen transport protein in animal bodies. However, there is a paucity of information regarding differences between alpha and beta subunits of hemoglobin in terms of oxygen affinity. The sequential model of Koshland, Nemthy and Filmer (KNF model) has attributed similar affinities to both alpha and beta subunits. The main purpose of the present study is to construct a ...
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The contribution of the porphyrin skeleton to the potential energy surface metalloporphyrins is calculated by the semiempirical method of quantum mechanical extension of the consistent force field to eta electron molecules. This calculation makes it possible to correlate the observed structure of metalloporphyrins with the strain energy of the porphyrin skeleton. It is found that the out-of-pla...
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Equilibrium measurements of oxygen binding by 0 iron(II) and cobalt(II) picket fence porphyrins exhibit p^2, ΔΗ°, and AS° values close to those of myoglobin and cobalt myoglobin respectively. In contrast the CO affinities of simple iron(II) porphyrins are much greater than those of the hemoproteins, hemoglobin (Hb) and myoglobin (Mb). This difference is apparently caused by distal residues in H...
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ژورنال
عنوان ژورنال: Biophysical Journal
سال: 1989
ISSN: 0006-3495
DOI: 10.1016/s0006-3495(89)82648-7