title: Local perturbation of the double helical DNA structure near single breaks.
abstract: The influences of DNA composition and solvent modification on the stability of the native DNA structure near a single break have been studied. The value of the magnification parameter h of the double helix breakdown probability in a haplotomic degradation process is used as an index of the perturbation range. Methodological and technical details are discussed and comments are made on previously reported data on the h value. From this study it may be concluded that the width of the perturbation zone next to a nick is influenced by solvent-induced changes in the general stability of the native DNA molecule, and by compositional-dependent local interactions. Our results point to entropic effects as the more important contributions to stability perturbation near a discontinuity in the native DNA molecule.
mesh_terms: D004269:DNA, Bacterial / Q000378:metabolism* / Q000528:radiation effects; D003851:Deoxyribonucleases; D003854:Deoxyribonucleotides; D005720:Gamma Rays; D008956:Models, Chemical; D009690:Nucleic Acid Conformation; D010636:Phenols; D013696:Temperature
chemical_list: D004269:DNA, Bacterial; D003854:Deoxyribonucleotides; D010636:Phenols; D003851:Deoxyribonucleases