title: Studying the effect of a charged surface on the interaction of bleomycin with DNA using an atomic force microscope.
abstract: The cleavage of DNA caused by the antitumoral drug bleomycin has been investigated using atomic force microscopy (AFM). This work deals with the effect that adsorbing DNA onto a positively- or negatively-charged surface has on the double-strand cleavage of DNA by Fe(III)/bleomycin. Quantitative analysis of the number of breaks per DNA molecule, in bulk and at the surface of the mica substrate, has been performed by analyzing AFM images. It turns out that the cleavage of DNA is strongly inhibited by a positively-charged surface. Our experiments can be interpreted using a simple electrostatic model. This paper is a first step in the study of DNA accessibility to ligand such as bleomycin, using AFM in liquids.
authors.affiliation: Laboratoire de Microscopie Moléculaire et Cellulaire, UMR 8126 CNRS-IGR-UPS, Institut Gustave-Roussy, 39 rue Camille Desmoulins, 94805 Villejuif Cedex, France. Olivier.Pietrement@igr.fr
authors.forename: Olivier
authors.initials: O
authors.lastname: Piétrement
authors.forename: David
authors.initials: D
authors.lastname: Pastré
authors.forename: Fabrice
authors.initials: F
authors.lastname: Landousy
authors.forename: Marie-Odile
authors.initials: MO
authors.lastname: David
authors.forename: Stéphane
authors.initials: S
authors.lastname: Fusil
authors.forename: Loïc
authors.initials: L
authors.lastname: Hamon
authors.forename: Alain
authors.initials: A
authors.lastname: Zozime
authors.forename: Eric
authors.initials: E
authors.lastname: Le Cam
mesh_terms: D000327:Adsorption; D000538:Aluminum Silicates / Q000737:chemistry*; D001761:Bleomycin / Q000737:chemistry*; D020099:Coated Materials, Biocompatible / Q000032:analysis / Q000737:chemistry*; D004247:DNA / Q000737:chemistry* / Q000648:ultrastructure*; D004249:DNA Damage; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008422:Materials Testing; D018625:Microscopy, Atomic Force / Q000379:methods*; D055672:Static Electricity; D013499:Surface Properties
chemical_list: D000538:Aluminum Silicates; D020099:Coated Materials, Biocompatible; D001761:Bleomycin; D004247:DNA; C011934:mica