title: Dynamic Chemistry of Disulfide Terminated Oligonucleotides in Duplexes and Double-Crossover Tiles.
abstract: Designed nanostructures formed by self-assembly of multiple DNA strands suffer from low stability at elevated temperature and under other denaturing conditions. Here, we propose a method for covalent coupling of DNA strands in such structures by the formation of disulfide bonds; this allows disassembly of the structure under reducing conditions. The dynamic chemistry of disulfides and thiols was applied to crosslink DNA strands with terminal disulfide modifications. The formation of disulfide-linked DNA duplexes consisting of three strands is demonstrated, as well as a more-complex DNA double-crossover tile. All the strands in the fully disulfide-linked structures are covalently and geometrically interlocked, and it is demonstrated that the structures are stable under heating and in the presence of denaturants. Such a reversible system can be exploited in applications where higher DNA stability is needed only temporarily, such as delivery of cargoes to cells by DNA nanostructures.
authors.affiliation: Danish National Research Foundation, Center for DNA Nanotechnology, Department of Chemistry and iNANO, Gustav Wieds Vej 14, 8000 Aarhus C, Denmark.
authors.forename: Mattia
authors.initials: M
authors.lastname: De Stefano
authors.affiliation: Danish National Research Foundation, Center for DNA Nanotechnology, Department of Chemistry and iNANO, Gustav Wieds Vej 14, 8000 Aarhus C, Denmark. kvg@chem.au.dk.
authors.forename: Kurt
authors.initials: K
authors.lastname: Vesterager Gothelf
mesh_terms: D004247:DNA / Q000138:chemical synthesis / Q000737:chemistry; D004220:Disulfides / Q000737:chemistry*; D004591:Electrophoresis, Polyacrylamide Gel; D049329:Nanostructures / Q000737:chemistry*; D009841:Oligonucleotides / Q000737:chemistry*
chemical_list: D004220:Disulfides; D009841:Oligonucleotides; D004247:DNA
keywords: DNA structures; disulfides; dynamic combinatorial chemistry; nucleic acids; reduction