title: Effects of a 8-oxoadenosine incorporation on quadruplex structures: thermal stabilities and structural studies.
abstract: The effects of incorporation of 8-oxoadenosine in two different truncations of human telomeric sequence forming quadruplex structures are reported. In order to characterise their structures, a combination of NMR and UV spectroscopy and computational techniques were used. Both oligonucleotides have been found to form fourfold symmetric quadruplex structures. As a tautomeric equilibrium between keto and enol forms of 8-oxoadenosine may establish in solution and intrinsic stabilities effects, such as internal H-bonds, for example, may determine the predominance of some particular tautomer, molecular modelling studies were performed on quadruplex structures containing both the tautomeric forms. Both molecules resulted to be thermally less stable than the natural.
authors.affiliation: Dipartimento di Chimica delle Sostanze Naturali, Università degli Studi di Napoli Federico II, Napoli, Italy.
authors.forename: Veronica
authors.initials: V
authors.lastname: Esposito
authors.forename: Antonio
authors.initials: A
authors.lastname: Randazzo
authors.forename: Antonella
authors.initials: A
authors.lastname: Virgilio
authors.forename: Luca
authors.initials: L
authors.lastname: Cozzuto
authors.forename: Luciano
authors.initials: L
authors.lastname: Mayol
mesh_terms: D000241:Adenosine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000494:pharmacology; D006358:Hot Temperature; D006801:Humans; D006860:Hydrogen Bonding; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical; D008958:Models, Molecular; D008968:Molecular Conformation; D009690:Nucleic Acid Conformation; D009691:Nucleic Acid Denaturation; D009838:Oligodeoxyribonucleotides / Q000737:chemistry; D018384:Oxidative Stress; D012984:Software; D013053:Spectrophotometry; D016615:Telomere / Q000737:chemistry; D013696:Temperature; D014466:Ultraviolet Rays
chemical_list: D009838:Oligodeoxyribonucleotides; C036009:8-oxoadenosine; D000241:Adenosine