title: Analysis of actinomycin D-DNA model complexes using a quantum-chemical criterion: Mulliken overlap populations.
abstract: The binding of the antitumoral drug actinomycin D to single- and double-stranded DNA was investigated using molecular modeling in the frame of MM+ molecular mechanics and AM1 semi-empirical method. Two other programs, especially conceived to analyze hydrogen-bonding patterns in biological macromolecules, HBexplore, based on geometrical criteria and SHB_interactions, based on quantum-chemical criteria (Mulliken overlap populations), were also used. The results account for the non-cooperative intercalative binding process previously investigated, and outline the contribution of specific hydrogen bonding as well as CH...O(N) and other atom-atom intermolecular interactions to the stabilization of the actinomycin D-DNA complexes. They also support the hemi-intercalation model proposed in literature for the actinomycin D-ssDNA complex.
authors.affiliation: Department of Physical Chemistry, Faculty of Chemistry, University of Bucharest, Blvd. Elisabeta 4-12, Bucharest RO-70346, Romania.
authors.forename: Cezar
authors.initials: C
authors.lastname: Bendic
authors.forename: Mirela
authors.initials: M
authors.lastname: Enache
authors.forename: Elena
authors.initials: E
authors.lastname: Volanschi
mesh_terms: D004247:DNA / Q000737:chemistry* / Q000378:metabolism; D043542:DNA, Z-Form / Q000737:chemistry* / Q000378:metabolism; D003609:Dactinomycin / Q000737:chemistry* / Q000378:metabolism; D006860:Hydrogen Bonding; D008956:Models, Chemical; D008958:Models, Molecular; D009690:Nucleic Acid Conformation; D011789:Quantum Theory
chemical_list: D043542:DNA, Z-Form; D003609:Dactinomycin; D004247:DNA