Theoretical approaches to tracing conformational polymorphism of proteins.

Proteins are not the rigid, static entities as once suggested by early structural biology studies. Instead, they are highly dynamic molecules that are better represented not by a single reference structure, but by a Boltzmann ensemble of conformations. In this article, we review theoretical approaches to reproducing such structural ensembles, with particular emphasis on methods designed to identify major conformational states and the transition pathways connecting them.