An alternative theoretical formula for hemoglobin oxygenation.

Classical models of homotropic allostery are based on the postulate that the binding sites are equivalent in their ability to interconvert between high and low affinity states, but compelling evidence exists that the subunits of human hemoglobin are not simultaneously available for oxygen equilibration, thus reducing the number of possible intermediate microstates. The incorporation of these results into the Adair scheme reveals an alternative mechanism for hemoglobin oxygenation, not based on affinity changes.