Interaction of organoruthenium(II)-polypyridyl complexes with DNA and BSA.

The interaction of four arene ruthenium complexes [(η-p-cymene)Ru(Medppz)Cl]PF (1) with Medppz = 11,12-dimethyldipyrido[3,2-a:2',3'-c]phenazine, [(η-p-cymene)Ru(aip)Cl]PF (2) with aip = 2-(9-anthryl)-1H-imidazo[4,5-f][1,10] phenanthroline), ([(ƞ-toluene)Ru(ppf)Cl]PF) (3) and ([(ƞ-p-cymene)Ru(ppf)Cl]PF) (4) with ppf = pyrido[2',3':5,6] pyrazino[2,3-f][1,10]phenanthroline with calf thymus DNA were investigated. All of four complexes exhibit DNA-binding activity. UV-Vis spectroscopic studies revealed the intrinsic binding constants of the order 10 M of magnitude, indicating non-intercalative mode.

Tailor-made biocatalysts based on scarcely studied acidic horseradish peroxidase for biodegradation of reactive dyes.

Peroxidases (EC 1.11.1.

Acidic horseradish peroxidase activity abolishes genotoxicity of common dyes.

The aim of this study was to investigate the impact of dyes on DNA before and after enzymatic decolorization by acidic horseradish peroxidase (HRP-A). The comet assay is easy and feasible method widely used to measure DNA damage and repair. The medium-throughput comet assay was employed for assessment of genotoxic effects of 8 dyes in BEAS-2B cells.

Studies on the interactions of bioactive quinone avarone and its methylamino derivatives with calf thymus DNA.

The interactions of avarone, a quinone from the marine sponge Dysideaavara, and the methylamino derivatives of avarone (2), 3'-(methylamino)avarone (3) and 4'-(methylamino)avarone (4) with calf thymus DNA (CT-DNA) were studied. Agarose gel electrophoreticanalysis showed that binding of the quinones quenched fluorescence of ethidium bromide (EB). The extent of fluorescence quenching of intercalator EB by competitive displacement from EB-CT-DNA system and of groove binder Hoechst 33258 (H) from H-CT-DNA system with the quinones was analyzed by fluorescence spectroscopy.

Dexamethasone treatment affects nuclear glucocorticoid receptor and glucocorticoid response element binding activity in liver of rats (Rattus norvegicus) during aging.

Aging is associated with marked changes in the biochemical processes of many organs. Basal and glucocorticoid induced of liver nuclear glucocorticoid receptor (GR) on the level of protein expression and DNA-binding activity were investigated at different ages (3, 6, 12, 18 and 24 months old) in two groups of rats in: untreated and dexamethasone treated. The results showed a significant decline of GR protein immunopurified from untreated rats of advanced age.