Hydrogen bonding, stacking and cation binding of DNA bases

Ab initio, quantum chemical calculations with inclusion of electron correlation effects significantly contributed to our understanding of molecular interactions of DNA bases. Some of the most important findings are introduced in the present overview: nonplanarity of nucleobases, out-of-plane hydrogen bonds and amino acceptor interactions, structures and energies of hydrogen bonded base pairs, nature of base stacking, and interactions between metal cations and nucleobases. Also, accuracy of density functional theory, semi-empirical methods, distributed multipole analysis and empirical potentials is briefly commented on. (C) 2001 Elsevier Science B.V. All rights reserved.