title: Tetraplex formation of a guanine-containing nonameric DNA fragment.
abstract: A combination of spectroscopic and calorimetric techniques has been used to characterize the structures formed by a family of short, guanine-containing DNA single strands of the form d[GGTTXTTGG], X = A, C, G, T. In 1 molar NaCl at low temperatures, these molecules do not behave like single strands, but rather exhibit properties consistent with tetraplex formation. The standard state enthalpies, entropies, and free energies for formation of each tetraplex have been measured, as have preliminary nuclear magnetic resonance (NMR) spectra. In 1 molar KCl, the melting behavior of the structure or structures is more complex than in 1 molar NaCl. This observation may be related to the recently proposed "sodium-potassium switch."
authors.affiliation: Department of Chemistry, Rutgers, State University of New Jersey, Piscataway 08855.
authors.forename: R Z
authors.initials: RZ
authors.lastname: Jin
authors.forename: K J
authors.initials: KJ
authors.lastname: Breslauer
authors.forename: R A
authors.initials: RA
authors.lastname: Jones
authors.forename: B L
authors.initials: BL
authors.lastname: Gaffney
mesh_terms: D001483:Base Sequence; D004247:DNA / Q000737:chemistry*; D006147:Guanine; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D009838:Oligodeoxyribonucleotides / Q000737:chemistry; D012091:Repetitive Sequences, Nucleic Acid; D013696:Temperature; D013816:Thermodynamics
chemical_list: D009838:Oligodeoxyribonucleotides; D006147:Guanine; D004247:DNA