Hemoglobin adaptation

Powers, D.A. (1972). Hemoglobin adaptations for fast and slow water habitats in sympatric catasto-mid fishes. Science 177 360-362. 

Weber, R. (1995). Hemoglobin adaptations to hypoxia and altitude—the phylogenetic perspective. In Hypoxia and the Brain, pp. 31-44, ed. 

Figure 5. Peptide maps of tryptic digests of normal and sickle cell hemoglobins. Adapted from Ref. 73. The single peptide difference between the two hemoglobins is indicated by shying and...

An article entitled "Hemoglobin Its Occurrence, Structure, and Adaptation" appeared in the March 1982 issue of the Journal of Chemical Education (pp. 173-178). 

The properties of individual hemoglobins are consequences of their quaternary as well as of their secondary and tertiary structures. The quaternary structure of hemoglobin confers striking additional properties, absent from monomeric myoglobin, which adapts it to its unique biologic roles. The allosteric (Gk alios other, steros space ) properties of hemoglobin provide, in addition, a model for understanding other allosteric proteins (see Chapter 11). 

Many analytical techniques have been used to study deoxy- and oxymyoglobin and hemoglobin and their model compounds. A summary of these techniques, adapted... 

Fig. 45. Effect of oxygenation of Hemoglobin M -B(B2A6,w-0h)on one of the histidine i4N-EN-DOR lines (Washed whole cells). (Adapted from Ref. 243)...

Isotherm Subtraction. A second method (7) of determining the net proton coefficient from adsorption data is an adaptation of the thermodynamics of linked functions as applied to the binding of gases to hemoglobin (19). The net proton coefficient determined by this method is designated, Xp- The computational procedure makes a clear distinction between the influence of adsorption density and pH on the magnitude of the net proton coefficient. The fundamental equation used in the calculation of Xp is... 

This method is an adaptation of the thermodynamic analysis of linked functions, the binding of multiple ligands to macromolecules (e.g., Wyman, 19) and the binding of gases to hemoglobin. 

A similar adaptive mutation is found in human fetal hemoglobin. This has a lower oxygen affinity than the adult in the absence of phosphate, but it also has a lower affinity for DPG, due mainly to the replacement His H21(143)/3 — Ser. As a result, the oxygen affinity of fetal blood exceeds that of the adult, which helps the transfer of oxygen from the maternal to the fetal circulation across the placenta (5). 

BPG levels are elevated In the RBCs of persons who have adapted to high altitude conditions, enhancing dissociation of02 In tissues to compensate for reduced O2 saturation of hemoglobin. 

Similarly, iron is an essential mineral in hemoglobin that is required to transport oxygen. It is also an essential nutrient in bone marrow, liver, and spleen. Iron deficiency, for example, in cases of anemia, is therefore routinely supplemented with ferrous sulfate or a variety of other iron-based compounds. If its supplementation is not urgent, it can also be replenished by adapting iron-rich diets. Prescribed iron supplements feature in the top 200 most prescribed dmgs in the United States only in 2004 (Table 1.17). 

To adapt the Hill equation to the binding of oxygen to hemoglobin we must again substitute p02 for [L] and Pso for Kd ... 

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