From Minimal Models to Real Proteins: Time Scales for Protein Folding Kinetics

The multipathway mechanism discovered using minimal protein models in conjunction with scaling arguments are used to obtain time scales for the various processes in the folding of real proteins. We consider pathways involving low energy native-like structures as well as direct pathways that proceed via a nucleation mechanism. The average activation barrier separating the low energy structures and the native state is predicted to scale as √N where N is the number of aminoacids in the proteins. In addition estimates of folding times for direct pathways in which collapse and folding are (almost) synchronous are given. It is argued folding sequences whose folding transition temperature is very close to the collapse transition temperature are likely to reach the native conformation rapidly.