the interaction between isatin-β-thiosemicarbazone (ibt) and calf thymus dna (ct-dna) was investigated in physiological buffer (ph 7.4) using neutral red (nr) dye as a spectral probe by uv–vis absorption and fluorescence spectroscopy, as well as viscosity measurements. the ibt is stabilized by intercalation in the dna ( k [ibt –dna] =1.03×105 m−1), and displaces the nr dye from the nr–dna comple...

The complex of bis-(p-aminobnzoato)tetraquamanganese(II) was synthesized according to the literature method. The interaction between bis-(p-aminobnzoato)tetraquamanganese(II) and cat genomic DNA was studied by gel electrophoresis, fluorescence spectroscopy, UV-visible and viscosity methods. The results suggest that the complex binds with DNA by intercalating through the ligand. The intrinsic bi...

Discrimination of phosphomonoesters and phosphodiesters of DNA was attempted with naphthalene diimide carrying two zinc-dipicolylamine (Dpa) units (1). The binding constant of 1 for a self-complementary octanucleotide was 1.3×10(6)M(-1), while the value for the phosphorylated counterpart was 4.8×10(6)M(-1). This fourfold increase in the binding constant seems to stem from higher affinity of the...

Anilinonaphthalenesulfonate (ANS) and tryptophan compete for binding to the trp repressor protein; thus, the fluorescence decrease associated with ANS dissociation can be used as a fluorometric marker for tryptophan binding to the protein. Using this approach, the tryptophan equilibrium dissociation constant was measured at 25 degrees C to be 3.7 (+/- 1.2) X 10(-5) M, a value which compares fav...

Yolk proteins purified from the nematode Caenorhabditis elegans, from the frog Xenopus laevis, and from chicken eggs all have the unexpected property of binding strongly and preferentially to a left-handed Z-DNA probe, brominated poly(dG-dC). We estimate that the nematode proteins bind to Z-DNA with an association constant of at least 10(4) (M-1) and that this association constant is at least 4...

Deoxyribonucleic acid (DNA) is an important molecular target for anti-cancer agents due to its involvement in gene expression and protein synthesis which are fundamental steps in cell division and growth. A number of antineoplastic agents interfere with DNA and hence disturb the cell cycle. Compounds including planar aromatic rings are privileged scaffolds in binding to the DNA. This characteri...

We present a novel method for fabricating unimolecular double-stranded DNA microarrays on solid surfaces, which were used to probe sequence-specific DNA/protein interactions. For manufacturing the unimolecular double-stranded DNA microarrays, two kinds of special single-stranded oligonucleotides, constant oligonucleotide and target oligonucleotide, were chemically synthesized. The constant olig...

Many transcription factors (TFs) have the ability to cooperate on DNA elements as heterodimers. Despite the significance of TF heterodimerization for gene regulation, a quantitative understanding of cooperativity between various TF dimer partners and its impact on heterodimer DNA binding specificity models is still lacking. Here, we used a novel integrative approach, combining microfluidics-ste...

the surface parameter of nanoparticles such as hydrophobicity and a hydrophilicity on protein structure and function is very important. in this study, conformational changes of glucose oxidase (gox) in the mercaptopurine: gnps and 11-mercaptoundecanoic acid: gnps as a hydrophobic and a hydrophilic gnps surface was investigated by various spectroscopic techniques, including: uv-vis absorption, f...

Deoxyribonucleic acid (DNA) is an important molecular target for anti-cancer agents due to its involvement in gene expression and protein synthesis which are fundamental steps in cell division and growth. A number of antineoplastic agents interfere with DNA and hence disturb the cell cycle. Compounds including planar aromatic rings are privileged scaffolds in binding to the DNA. This characteri...