A theoretical consideration of the influence of selective binding of small ligands on DNA helix-coil transition.

The influence of small ligands on DNA helix-coil transition is considered theoretically. The ligands are supposed to interact with DNA base pairs reversibly and selectively. The long-range ligand-ligand interactions are taken into account. Simple formulae are derived for calculation of melting curve alteration induced by ligand binding. The proposed theoretical approach requires neither knowledge of nucleotide sequence nor long computation time.