title: A cubic arrangement of DNA double helices based on nickel-guanine interactions.
abstract: DNA oligonucleotides can be used in order to assemble highly structured materials. Oligonucleotides with sticky ends can form long linear structures, whereas branching is required to form two- and three-dimensional nanostructures. In this paper, we show that when Ni(2+) is attached to the N7 atom of guanine, it can also act as a branching point. Thus, we have found that the heptanucleotide d(GAATTCG) can assemble into long linear duplex structures, which cross in space to generate a cubic structure. The three-dimensional arrays are stabilized by phosphate-Ni(2+)-guanine interactions. For the first time, the crystallization of a B form DNA oligonucleotide in a cubic system is reported, space group I23. Large solvent cavities are found among the DNA duplexes.
authors.affiliation: Departament d'Enginyeria Química, Universitat Politècnica de Catalunya, Avinguda Diagonal 647, E-08028 Barclelona, Spain.
authors.forename: Núria
authors.initials: N
authors.lastname: Valls
authors.forename: Isabel
authors.initials: I
authors.lastname: Usón
authors.forename: Catherine
authors.initials: C
authors.lastname: Gouyette
authors.forename: Juan A
authors.initials: JA
authors.lastname: Subirana
mesh_terms: D020029:Base Pairing; D002413:Cations, Divalent; D018360:Crystallography, X-Ray; D004247:DNA / Q000737:chemistry* / Q000378:metabolism; D006147:Guanine / Q000737:chemistry* / Q000378:metabolism; D008958:Models, Molecular; D009532:Nickel / Q000737:chemistry*; D009690:Nucleic Acid Conformation; D009841:Oligonucleotides / Q000737:chemistry / Q000378:metabolism; D012997:Solvents / Q000737:chemistry
chemical_list: D002413:Cations, Divalent; D009841:Oligonucleotides; D012997:Solvents; D006147:Guanine; D009532:Nickel; D004247:DNA