Nucleic acid duplexes containing non-Watson–Crick base pairs are of interest to several fields including structural biology, supramolecular chemistry, origin of life, and synthetic biology. An early observation of a natural non-Watson–Crick base pair was the tRNA–mRNA adenine–inosine wobble pair, and it is now known that purine–purine pairs occur frequently in natural RNAs, including ribosomes ...

Fluorescence spectroscopy and ultraviolet (UV) spectroscopy techniques coupled with cyclic voltammetry (CV) were used to study the interaction between salmon sperm DNA and 1,10-Phenanthroline cobalt(II) complex, [Co(phen)2(Cl)(H2O)]Cl·H2O, where phen = 1,10-phenanthroline. The interaction between [Co(phen)2(Cl)(H2O)] and doublestrand DNA (dsDNA) was identified to be intercalative mode. An elect...

A novel fluoranthene based fluorescent chemosensor for the detection of picric acid (PA) at the parts per billion (ppb) level was evaluated. Static fluorescence quenching was the dominant process by intercalative π-π interaction between fluoranthene (S(1)) and nitroaromatics.

BACKGROUND Binding of two 9-O-(ω-amino) alkyl ether berberine analogs BC1 and BC2 to the RNA triplex poly(U)(•)poly(A)(*)poly(U) was studied by various biophysical techniques. METHODOLOGY/PRINCIPAL FINDINGS Berberine analogs bind to the RNA triplex non-cooperatively. The affinity of binding was remarkably high by about 5 and 15 times, respectively, for BC1 and BC2 compared to berberine. The s...

We use a combination of spectroscopic, calorimetric, viscometric and computer modeling techniques to characterize the binding of the aminoglycoside antibiotic, tobramycin, to the polymeric RNA duplex, poly(rI).poly(rC), which exhibits the characteristic A-type conformation that is conserved among natural and synthetic double-helical RNA sequences. Our results reveal the following significant fe...

Porophyrins and their metal derivatives are strong DNA binders with association constant of  to  . Some of these compounds have been used for the radiations sensitization therapy of cancer and are targeted to interact with cellular DNA. Binding of porphyrins to DNA changes the expectral and other physic chemical characteristic of porphyrins, The mode of binding can be extracted from inspection ...

Two new antitumour drugs, imide derivatives of 3-nitro-1,8-naphthalic acid having different basic side chains linked to the imide nitrogen, have been shown to bind to double-helical DNA by intercalation. At ionic strength 0.01 mol/litre, pH 7, their intrinsic association constants are about 1.45 x 10(5) M-1 and each bound ligand molecule occludes about 3.4 nucleotides of the DNA lattice. They r...

The interaction between 4',6-diamidino-2-phenylindole (DAPI) and the DNA oligomer [d(CGACGTCG)]2 has been investigated by proton one- and two-dimensional NMR spectroscopy in solution. Compared with the minor groove binding of the drug to [d(GCGATCGC)]2, previously studied by NMR spectroscopy, the interaction of DAPI with [d(CGACGTCG)]2 appears markedly different and gives results typical of a b...

The interaction of ethidium, a DNA intercalator, with the poly(dA).poly(dT) duplex and the poly (dA).2poly(dT) triplex has been investigated by a variety of spectrophotometric and hydrodynamic techniques. The fluorescence of ethidium is increased when either the duplex or triplex form is present. Binding constants, determined from absorbance measurements, indicate that binding to the triple hel...