title: Light-induced surface wettability of a tethered DNA base.
abstract: We show that the DNA base thymine and other uracil derivatives, when alkylated with a hydrocarbon chain and assembled at a gold interface, dimerize when subjected to UV irradiation. The process is robust and reversible and is accompanied by a substantial decrease in wettability as well as a marked decrease in acidity constant when the dimer is formed. There is a concerted molecular reorientation that accompanies photodimerization, with the dimer displaying a marked affinity for the gold surface. The spatial requirements for this reorganization are satisfied during dimerization by the reduction in intermolecular distance that occurs when the cyclobutane ring is formed between adjacent bases. The structural changes observed here for a tethered DNA base provide a direct route for exploring reactions, in two dimensions, that are of central interest in biology.
authors.affiliation: Ian Wark Research Institute, University of South Australia, Mawson Lakes Campus, Adelaide.
authors.forename: Nicola
authors.initials: N
authors.lastname: Lake
authors.forename: John
authors.initials: J
authors.lastname: Ralston
authors.forename: Geoffrey
authors.initials: G
authors.lastname: Reynolds
mesh_terms: D004247:DNA / Q000737:chemistry; D019281:Dimerization; D008027:Light; D013941:Thymine / Q000737:chemistry; D014466:Ultraviolet Rays; D014498:Uracil / Q000737:chemistry; D017155:Wettability
chemical_list: D014498:Uracil; D004247:DNA; D013941:Thymine