Calorimetric studies of drug-DNA interactions

Summary Calorimetric techniques are powerful tools for the study of the energetics involved in the conformational plasticity of nucleic acids and in their interaction with ligands. The techniques of ITC and DSC, described here, provide us with the universal measurement of the heat associated in these reactions and allows dissection of the free energy terms into their corresponding enthalpic and entropic contributions. They also provide additional extrathermodynamic data such as, but not limited to, stoichiometry of complexes, ion binding, and cooperativity. In this review we have tried to give the reader a brief overview and discussion on how to apply calorimetric techniques for the understanding of ligand binding to DNA by using typical examples on the ligand mode of binding, ligand sequence specificity, the novel binding of ligands to hairpin loops, and the interaction of ligands to nonclassical DNA structures of current biological importance.