Modified thrombin-binding aptamers carrying 2'-deoxyguanine (dG) residues with locked North- or South-bicyclo[3.1.0]hexane pseudosugars were synthesized. Individual 2'-deoxyguanosines at positions dG5, dG10, dG14 and dG15 of the aptamer were replaced by these analogues where the North/anti and South/syn conformational states were confined. It was found that… (More)
An aptamer-capped mesoporous material for the selective and sensitive detection of α-thrombin in human plasma and serum has been prepared and characterised.
The synthesis of oligomers containing two or three acridine units linked through 2-aminoethylglycine using solid-phase methodology is described. Subsequent studies on cell viability showed that these compounds are not cytotoxic. Binding to several DNA structures was studied by competitive dialysis, which showed a clear affinity for DNA sequences that form… (More)
Mono- and disaccharides have been shown to stack on top of DNA duplexes stabilizing sequences with terminal C-G base pairs. Here we present an apolar version of glucose and cellobiose as new capping agents that stack on DNA increasing considerably its stability with respect to their natural polyhydroxylated mono- and disaccharide DNA conjugates.
Cyclic oligonucleotides carrying an oligopurine Watson-Crick sequence linked to the corresponding (G,A)- and (G,T)-antiparallel strands were prepared by nonenzymatic template-assisted cyclization of phosphorylated precursors. Cyclization was attempted using 3'-phosphate and 5'-phosphate linear precursors with carbodiimide or BrCN activation. The best… (More)
The structure of G,T-parallel-stranded duplexes of DNA carrying similar amounts of adenine and guanine residues is studied by means of molecular dynamics (MD) simulations and UV- and CD spectroscopies. In addition the impact of the substitution of adenine by 8-aminoadenine and guanine by 8-aminoguanine is analyzed. The presence of 8-aminoadenine and… (More)
Human O(6)-alkylguanine-DNA alkyltransferase (hAGT) is a DNA repair protein that reverses the effects of alkylating agents by removing DNA adducts from the O(6) position of guanine. Here, we developed a real-time fluorescence hAGT activity assay that is based on the detection of conformational changes of the thrombin-binding aptamer (TBA). The quadruplex… (More)
Several acridine derivatives were synthesized and their anti-proliferative activity was determined. The most active molecules were derivatives of 5-methylacridine-4-carboxylic acid. The DNA binding properties of the synthesized acridines were analyzed by competitive dialysis and compared with the anti-proliferative activities. While inactive acridine… (More)
We present a novel approach to reversibly control the assembly of liposomes through an anchored multistimuli responsive DNA oligonucleotide decorated with an azobenzene moiety (AZO-ON1). We show that liposomes assembly can be simultaneously controlled by three external stimuli: light, Mg(2+), and temperature. (i) Light alters the interaction of AZO-ON1 with… (More)
Triplex stability is studied in crowding conditions using small cosolutes (ethanol, acetonitrile and dimethylsulfoxide) by ultraviolet (UV), circular dichroism (CD) and nuclear magnetic resonance (NMR) spectroscopies. The results indicate that the triplex is formed preferentially when the triplex forming oligonucleotide (TFO) is RNA. In addition, DNA… (More)