title: Isoguanine quartets formed by d(T4isoG4T4): tetraplex identification and stability.
abstract: The self-aggregation of the oligonucleotide d(T4isoG4T4) (1) is investigated. Based on ion exchange HPLC experiments and CD spectroscopy, a tetrameric structure is identified. This structure was formed in the presence of sodium ions and shows almost the same chromatographic mobility on ion exchange HPLC as d(T4G4T4) (2). The ratio of aggregate versus monomer is temperature dependent and the tetraplex of [d(T4isoG4T4)]4 is more stable than that of [d(T4G4T4)]4. A mixture of d(T4isoG4T4) and d(T4G4T4) forms mixed tetraplexes containing strands of d(T4isoG4T4) and d(T4G4T4).
authors.affiliation: Laboratorium für Organische und Bioorganische Chemie, Universität Osnabrück, Germany. fraseela@rz.uni-osnabrueck.de
authors.forename: F
authors.initials: F
authors.lastname: Seela
authors.forename: C
authors.initials: C
authors.lastname: Wei
authors.forename: A
authors.initials: A
authors.lastname: Melenewski
mesh_terms: D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange; D002942:Circular Dichroism; D006147:Guanine / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet
chemical_list: D006147:Guanine; C008183:isoguanine