Nucleation-condensation protein folding model

The nucleation condensation model of protein folding (Chapter 2)... 

A key feature of the framework and nucleation-condensation models is the formation of secondary structure—which might or might not be coupled to the formation of tertiary structure—early in the folding process. It follows that a full description of the mechanism of protein folding also requires an understanding of the rules that stabilize molecular interactions in polypeptides. We consider these rules in Chapter 11. 

The notion that folding proceeds from a condensed state rather than from a random coil state is somewhat heretical in an age dominated by the secondary structure nucleation point of view. However, the question has not been addressed experimentally, and the Dill model is in accord with the thermodynamics of unfolding for many globular proteins. 

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