Monte Carlo simulations of protein-like heteropolymers

Properties of a simple model of polypeptide chains were studied by the mean s of the Monte Carlo method. The chains were built on the (310) hybrid latt ice. The residues interacted with long-range potential. There were two kind s of residues: hydrophobic and hydrophilic forming a typical helical patter n -HHPPHPP-. Short range potential was used to prefer helical conformations of the chain. It was found that at low temperatures the model chain formes dense and partially ordered structures (non-unique). The presence of the l ocal potential led to an increase of helicity. The effect of the interplay between the two potentials was studied. After the collapse of the chain fur ther annealing caused rearrangement of helical structures. Dynamic properti es of the chain at low temperature depended strongly on the local chain ord ering.