Monte Carlo Study of Substrate-Induced Folding and Refolding of Lattice Proteins

Many proteins can switch from one conformation to another under the influence of an external driving force, such as the binding to a specific substrate. Using a simple lattice model we show that it is feasible to design protein-like lattice proteins that can have two different conformations, depending on whether or not they are bound to a substrate. We give three different examples of such substrate-induced refolding. In addition, we have explored substrate-induced folding of lattice proteins that do not fold when free in solution. We show that such proteins can bind with the same high specificity as prefolded protein, but have a considerably lower binding free energy. In this way proteins can bind to a substrate in a way that is highly specific, yet reversible.