EVOLUTION OF MODEL PROTEINS ON A FOLDABILITY LANDSCAPE

We model the evolution of simple lattice proteins as a random walk in a fitness landscape, where the fitness represents the ability of the p rotein to fold. At higher selective pressure, the evolutionary traject ories are confined to neutral networks where the native structure is c onserved and the dynamics are non self-averaging and nonexponential. T he optimizability of the corresponding native structure has a strong e ffect on the size of these neutral networks and thus on the nature of the evolutionary process. (C) 1997 Wiley-Liss, Inc.