Stereo-electronic effects in polynucleotides and their double helices

Considerable attention has been focused on the DNA double helix, especially on the properties of its nucleotidic bases, but little attention has been paid to the role of the 2-deoxyribosyl moiety. The available computer-assisted theoretical methods have not been entirely helpful in enabling researchers to identify new stereo-electronic interactions within the polynucleotide strand, because of the way these programs are parameterized. An investigation, using the molecular modeling program STR3DI32.EXE, has identified several new interactions between the nucleotidic bases and the 2-deoxyribosyl moiety. These interactions are significant enough to enable us to recognize the unique role of the 2-deoxyribosyl moiety in the structure and stability of DNA. q 2004 Elsevier B.V. All rights reserved.