title: Elasticity of cisplatin-bound DNA reveals the degree of cisplatin binding.
abstract: Cisplatin was incidentally discovered to suppress cell division and became one of the most successful antitumor drugs. It is therapeutically active upon binding to DNA and locally kinking it. We demonstrate that after a bimodal modeling, the degree of platination of a single DNA molecule can be consistently and reliably estimated from elasticity measurements performed with magnetic tweezers. We predicted and measured for the first time two separate persistence lengths of kinked DNA at high and low tensions. We also directly observed that the degree of platination of DNA strongly depends on the concentration of sodium chloride as required for cisplatin's intracellular activity. Our study shows that micromanipulation techniques accurately reveal the degree of chemical modification of DNA which can be used for a new type of structure-sensitive biosensors.
authors.affiliation: Institute of Fundamental Physics, Department of Physics, Sejong University, Seoul 143-743, Korea.
authors.forename: Nam-Kyung
authors.initials: NK
authors.lastname: Lee
authors.forename: Jin-Sung
authors.initials: JS
authors.lastname: Park
authors.forename: Albert
authors.initials: A
authors.lastname: Johner
authors.forename: Sergei
authors.initials: S
authors.lastname: Obukhov
authors.forename: Ju-Yong
authors.initials: JY
authors.lastname: Hyon
authors.forename: Kyoung J
authors.initials: KJ
authors.lastname: Lee
authors.forename: Seok-Cheol
authors.initials: SC
authors.lastname: Hong
mesh_terms: D000970:Antineoplastic Agents / Q000737:chemistry / Q000378:metabolism; D002945:Cisplatin / Q000737:chemistry* / Q000378:metabolism; D004247:DNA / Q000737:chemistry* / Q000378:metabolism; D018736:DNA Adducts / Q000737:chemistry* / Q000378:metabolism; D004548:Elasticity; D008956:Models, Chemical; D008958:Models, Molecular; D009690:Nucleic Acid Conformation
chemical_list: D000970:Antineoplastic Agents; D018736:DNA Adducts; C057270:cisplatin-DNA adduct; D004247:DNA; D002945:Cisplatin