title: Structure of the DNA duplex d(ATTAAT)2 with Hoogsteen hydrogen bonds.
abstract: The traditional Watson-Crick base pairs in DNA may occasionally adopt a Hoogsteen conformation, with a different organization of hydrogen bonds. Previous crystal structures have shown that the Hoogsteen conformation is favored in alternating AT sequences of DNA. Here we present new data for a different sequence, d(ATTAAT)2, which is also found in the Hoogsteen conformation. Thus we demonstrate that other all-AT sequences of DNA with a different sequence may be found in the Hoogsteen conformation. We conclude that any all-AT sequence might acquire this conformation under appropriate conditions. We also compare the detailed features of DNA in either the Hoogsteen or Watson-Crick conformations.
authors.affiliation: Universitat Politècnica de Catalunya, Departament d'Enginyeria Química, Diagonal 647, E-08028, Barcelona, Spain.
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Acosta-Reyes
authors.affiliation: Universitat Politècnica de Catalunya, Departament d'Enginyeria Química, Diagonal 647, E-08028, Barcelona, Spain.
authors.forename: Elida
authors.initials: E
authors.lastname: Alechaga
authors.affiliation: Universitat Politècnica de Catalunya, Departament d'Enginyeria Química, Diagonal 647, E-08028, Barcelona, Spain.
authors.forename: Juan A
authors.initials: JA
authors.lastname: Subirana
authors.affiliation: Universitat Politècnica de Catalunya, Departament d'Enginyeria Química, Diagonal 647, E-08028, Barcelona, Spain.
authors.forename: J Lourdes
authors.initials: JL
authors.lastname: Campos
mesh_terms: D020029:Base Pairing; D004247:DNA / Q000737:chemistry*; D006860:Hydrogen Bonding
chemical_list: D004247:DNA