Cooperativity consilient mechanism

Immediately below, we note the historical case of oxygen transport by hemoglobin from lungs to the tissues and note how this would be discussed in terms of the consilient mechanism. This was the first biological system appreciated for its positive cooperativity, the cooperative binding of oxygen molecules that is key to successful transport. 

To the best of my knowledge, the hemoglobin oxygenation curve is historically the first example of a biologically essential positive cooperativity. Because of this, it becomes an important objective to explore the phenomenology of hemoglobin s positive cooperativity and compare it with that of the consilient mechanism due to an apolar-polar repulsive free energy of hydration (as is done in Chapter 7) and, in fact, to do so for a number of protein-based machines that exhibit positive cooperativity. 

Should the structural data show the a p -a p interface to be one of hydrophobic association that is disrupted on oxygenation, then in our view the answer is clearly yes, the cooperative binding of oxygen to hemoglobin results from the consilient mechanism. In our view the presence of hydrophobic association at the a P -a P interface would indicate that positive cooperativity, essential to hemoglobin function in oxygen transport, arises due to the consilient... 

The phenomenological experimental foundation for the challenging new perspectives presented by the hydrophobic and elastic consilient mechanisms stands on the successful design of model proteins capable of the extraordinarily diverse set of energy conversions noted above. The mechanistic foundation derives from the need to obtain explanation for otherwise inexplicable experimental results, such as stretch-induced pKa shifts, hydrophobic-induced pKa shifts, hydrophobic-induced reduction potential shifts, and systematic increases in steepness (positive cooperativity) of the experimental curves that follow the change... 

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