Multi-dimensional mapping and folding properties for non-classical helix-stabilizing interactions of proteins

By using a dynamical systems approach we investigate a model for helix-coil phase transition for polypeptides and proteins in the thermodynamic limit on recursive zigzag ladder with three-site interaction. We explicitly take into account a non-classical helix-stabilizing term (hydrogen bonds between CαH⋯O). We obtain folding and quasi-unfolding of the order parameter (degree of helicity Θ).