Phase transitions in homogeneous biopolymers: basic concepts and methods

Abstract

The basic models of helix-coil transitions in biomolecules are introduced. These include phenomenological, zipper (Bragg-Zimm) models of polypeptides, loop-entropy (Poland-Scheraga) and Hamiltonian (Peyrard-Bishop) models of homogeneous DNA denaturation. The transfer integral approach to one-dimensional thermodynamics is presented in some detail, including the necessary extensions to deal with the singular integral equations arising in the case of on-site potentials with a flat top. The (non-)applicability of the theorems which prohibit phase transitions in one-dimensional systems is discussed.