title: DNA interaction with palladium chelates of biogenic polyamines using atomic force microscopy and voltammetric characterization.
abstract: The interaction of double-stranded DNA with two polynuclear Pd(II) chelates with the biogenic polyamines spermidine (Spd) and spermine (Spm), Pd(II)-Spd and Pd(II)-Spm, as well as with the free ligands Spd and Spm, was studied using atomic force microscopy (AFM) at a highly oriented pyrolytic graphite (HOPG) surface, voltammetry at a glassy carbon (GC) electrode, and gel electrophoresis. The AFM and voltammetric results showed that the interaction of Spd and Spm with DNA occurred even for a low concentration of polyamines and caused no oxidative damage to DNA. The Pd(II)-Spd and Pd(II)-Spm complexes were found to induce greater morphological changes in the dsDNA conformation, when compared with their ligands. The interaction was specific, inducing distortion and local denaturation of the B-DNA structure with release of some guanine bases. The DNA strands partially opened give rise to palladium intra- and interstrand cross-links, leading to the formation of DNA adducts and aggregates, particularly in the case of the Pd(II)-Spd complex.
authors.affiliation: Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade de Coimbra, Portugal.
authors.forename: O
authors.initials: O
authors.lastname: Corduneanu
authors.forename: A-M
authors.initials: AM
authors.lastname: Chiorcea-Paquim
authors.forename: V
authors.initials: V
authors.lastname: Diculescu
authors.forename: S M
authors.initials: SM
authors.lastname: Fiuza
authors.forename: M P M
authors.initials: MP
authors.lastname: Marques
authors.forename: A M
authors.initials: AM
authors.lastname: Oliveira-Brett
mesh_terms: D000818:Animals; D015317:Biogenic Polyamines / Q000737:chemistry*; D002244:Carbon / Q000737:chemistry; D002417:Cattle; D002614:Chelating Agents / Q000737:chemistry*; D004247:DNA / Q000737:chemistry / Q000378:metabolism*; D004563:Electrochemistry; D004566:Electrodes; D004586:Electrophoresis; D005898:Glass / Q000737:chemistry; D006108:Graphite / Q000737:chemistry; D008024:Ligands; D018625:Microscopy, Atomic Force; D008958:Models, Molecular; D009690:Nucleic Acid Conformation; D009942:Organometallic Compounds / Q000737:chemistry* / Q000378:metabolism*; D010084:Oxidation-Reduction; D010165:Palladium / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D015317:Biogenic Polyamines; D002614:Chelating Agents; D008024:Ligands; D009942:Organometallic Compounds; C009139:pyrolytic carbon; D010165:Palladium; D002244:Carbon; D006108:Graphite; D004247:DNA