Metastability of the folded states of globular proteins.

The possibility that several metastable minima exist in which the folded forms of a polypeptide chain have similar structural characteristics but different energies is suggested. The validity of this hypothesis is illustrated with the aid of simulation methods on a model protein that folds into a beta-barrel structure. Some implications of this hypothesis such as the existence of multiple pathways with intermediates for protein folding are discussed.