title: Effects of cosolutes on the thermodynamic stability of parallel DNA duplex and triplex.
abstract: We investigated molecular crowding effects on the thermodynamic stability of Hoogsteen and Watson-Crick base pairs in an intramolecular duplex and triplex. The melting temperature (Tm) of Hoogsteen base pair formations in the triplex and the duplex increased 3.7 degrees C and 3.2 degrees C, respectively, by adding 20 wt% PEG 200. On the other hand, the Tm of Watson-Crick base pair formations in the triplex and the duplex decreased 5.7 degrees C and 5.2 degrees C, respectively. These results suggested that molecular crowding conditions generally stabilized and destabilized Hoogsteen and Watson-Crick base pairs, respectively, even in the different DNA structures.
authors.affiliation: Department of Chemistry, Faculty of Science and Engineering, Konan University 8-9-1 Okamoto, Higashinada-ku, Kobe 658-8501, Japan.
authors.forename: Kaori
authors.initials: K
authors.lastname: Nakamura
authors.forename: Hisae
authors.initials: H
authors.lastname: Karimata
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Ohmichi
authors.forename: Daisuke
authors.initials: D
authors.lastname: Miyoshi
authors.forename: Naoki
authors.initials: N
authors.lastname: Sugimoto
mesh_terms: D020029:Base Pairing; D004247:DNA / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry; D013816:Thermodynamics
chemical_list: C051802:triplex DNA; D011092:Polyethylene Glycols; D004247:DNA