Polypeptide chain collapse and protein folding

Polypeptide chain collapse is an integral component of a protein folding reaction. In this review, experimental characterization of the interplay of polypeptide chain collapse, secondary structure formation, consolidation of the hydrophobic core and the development of tertiary interactions, is scrutinized. In particular, the polypeptide chain collapse reaction is examined in the context of the three phenomenological models of protein folding – the hydrophobic collapse model, the framework model and the nucleation condensation model – which describe different ways by which polypeptide chains are able to fold in biologically relevant time-scales.

► Folding appears to begin by non-specific polypeptide chain collapse.
► Non-specific chain collapse is followed by a specific structure forming reaction in the first millisecond.
► The chain collapse reaction appears to be gradual in nature.