A Sample of Experimental Data

The most important point to bear in mind when examining binding data of Hb is that the Hb molecule does not operate in vacuum, nor in a pure one-component solvent. The molecular composition of the environment of the Hb molecule can have a decisive role in determining the efficiency of its function. In particular, the utility function, as determined by the pressure difference under which Hb operates, can change substantially when we vary the temperature, the pH, or the composition of the solvent (see the next subsection). 

From the general shape of the curves one gets the impression that the overall cooperativity of the Hb (under these specific conditions) decreases with increase in temperature. This impression is correct in general. However, if we look more closely at the various correlations in the system we see some temperature dependence that does not conform to this general trend. 

No general trend is observed in these nonadditivities. It is noteworthy, however. 

Correlation Functions for Human Adult Hb at Different Temperatures  

Free Energies and Nonadditivities (in kcal/mol) of the Cooperativities for Bindii of Oxygen to Human Adult lib at Different Temperatures  

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