Protein folding: A bridge between physics and biology

Protein folding represents a bridge between the laws of physics and the res ults of the evolutionary pressure under which the character of biology has developed. Biological evolution selects only those sequences that fold into well-defined three-dimensional structures. The selected sequences appear t o meet the requirement of forming stable three-dimensional structures simul taneously with the requirement of folding quickly. This review presents the modern view of folding across a broad compass of physical and biological p henomena.