scholarly journals Affinity studies of hypocrellin B and mono-cysteine substituted hypocrellin B with CT-DNA using spectroscopic methods

2005 ◽  
Vol 19 (5,6) ◽  
pp. 259-266 ◽  
Author(s):  
Shaohua Wei ◽  
Jiahong Zhou ◽  
Yuying Feng ◽  
Deyin Huang ◽  
Xuesong Wang ◽  
...  
Keyword(s):  
Deoxyribonucleic Acid ◽  
Double Helix ◽  
Cd Spectroscopy ◽  
Base Stacking ◽  
Calf Thymus ◽  
Visible Spectra ◽  
Hypocrellin B ◽  
Uv Visible ◽  
Dna Double Helix ◽  
Ct Dna

The interaction of anticancer drug hypocrellin B (HB) and mono-cysteine substituted hypocrellin B (MCHB) with calf thymus deoxyribonucleic acid (CT-DNA) has been investigated using spectral methods. The results of UV–visible spectra showed that the HB and MCHB can intercalate into the base-stacking domain of the CT-DNA double helix. Further studies based on fluorescence spectroscopy and circular dichroism (CD) spectroscopy also supported the intercalation mechanism.

scholarly journals Synthesis, Crystal Structure, Spectroscopic and Antimicrobial Properties of Ruthenium Complexes of Vinyl Imidazole and 4-Ethylaminomethyl Pyridine Ligands

2021 ◽  
Vol 33 (4) ◽  
pp. 859-866
Author(s):  
Rinki Moni Kalita ◽  
Rahul Sarma Baruah ◽  
Chitrani Medhi
Keyword(s):  
Ruthenium Complexes ◽  
Antimicrobial Properties ◽  
Spectral Shift ◽  
Electrochemical Studies ◽  
Biological Reduction ◽  
Pyridine Ligands ◽  
Calf Thymus ◽  
Visible Spectra ◽  
Uv Visible ◽  
Ct Dna

Ruthenium complexes of vinylimidazole (VIMD) and 4-ethylaminomethyl pyridine (EMP) ligands were synthesized and characterized by XRD and spectroscopic methods. The binding of these Ru(IIII) complexes with calf thymus-DNA has been studied by UV-visible spectroscopic and electrochemical studies. A prominent increase in the intensity of fluorescence spectra of these complexes with CT-DNA was observed and a distinct UV-visible spectral shift in presence of CT-DNA is probably due to an interaction of these complexes with CT-DNA. The evidence of DNA binding has been found from the change in the intensity of fluorescence and UV visible spectra. Also, the electron transfer ability of these complexes is very important in order to rationalize their activity towards the biological system therefore, we have studied the electrochemical studies of these complexes by using cyclic voltammetry. From this study, it is possible to draw some ideas on electrochemical potentials of the complexes relevant to biological reduction possibly Ru(III)/Ru(II). Both complexes were also tested for antimicrobial activity against bacterial strain and responses well as antimicrobial agent.

scholarly journals Interaction of Duloxetine Hydrochloride with Deoxyribonucleic Acid Measured by Fluorescence Spectroscopy

2016 ◽  
Vol 14 (2) ◽  
pp. 199-206
Author(s):  
Raznin Akter Joly ◽  
Md Reazul Islam ◽  
Sonia Sultana ◽  
Asma Rahman ◽  
Md Zakir Sultan ◽  
...  
Keyword(s):  
Fluorescence Spectroscopy ◽  
Deoxyribonucleic Acid ◽  
Antidepressant Drug ◽  
Living Organism ◽  
Binding Mode ◽  
Duloxetine Hydrochloride ◽  
Calf Thymus ◽  
Binding Forces ◽  
Ct Dna ◽  
Hypochromic Effect

Interactions with many clinically active therapeutic agents with DNA are well studied and it is necessary to decipher the structure of DNA and to investigate the pathological implications of those molecules in living organism. This study investigated the interaction of antidepressant drug Duloxetine-hydrochloride (DLX) with calf thymus DNA (ct-DNA). The interaction of DLX with ct-DNA was studied employing fluorescence spectroscopy. Hypochromic effect was found in the absorption spectra of duloxetine, and its wavelength had no shift in the presence of DNA indicating external binding mode of duloxetine to DNA. Fluorescence spectroscopic results showed the quenching of fluorescence intensity of DLX in presence of DNA indicating the interaction between DLX and DNA. Hydrophobic interaction and hydrogen bonding played the dominating role in DLX-DNA binding and binding forces also indicate the binding site of duloxetine to be at the minor groove of DNA.Dhaka Univ. J. Pharm. Sci. 14(2): 199-206, 2015 (December)

Stereoscopic Visualization of Spermidine-DNA Torus Structure Prepared by the Freeze-Fracture, Deep-Etch Technique

1981 ◽  
Vol 39 ◽  
pp. 438-439
Author(s):  
George C. Ruben ◽  
Kenneth A. Marx ◽  
Thomas C. Reynolds
Keyword(s):  
Double Helix ◽  
Freeze Fracture ◽  
Etching Technique ◽  
Calf Thymus ◽  
Quick Freezing ◽  
Metal Levels ◽  
Dna Strands ◽  
Dna Double Helix ◽  
Stereoscopic Visualization ◽  
Condensed Dna

Freeze-fracture TEM has been used to visualize spermidine-DNA complexes╌a model system for bacteriophage DNA packaging. We have observed the toroidal shape and bacteriophage size (770Å) of spermidine-condensed DNA particles prepared by quick freezing of DNA-spermidine solutions followed by a freeze-fracture, deep-etching technique. Single direction shadowing with low Pt-C metal levels (9Å thick) has allowed us to demonstrate that the freeze-fracture technique is capable of revealing the organization of separate double helical DNA strands on the torus surface. The spermidine-DNA toruses exhibited surface Pt-C decoration consistent with the DNA double helix being circumferentially wrapped to form the torus. In addition, we have demonstrated that a hydrated sample shows the same toroidal shapes that have been previously demonstrated by Chattoraj et. al, in a dehydrated preparation.We performed freeze-fracture TEM studies of spermidine condensed (0.2 mM) Calf Thymus DNA (5 μg/ml) complexes in 1 mM NaCl, 10 mM Tris pH 7.0. Samples were freeze-fractured and etched for 13 min at -97°C.

Interaction of Organophosphorus Insecticide Methylparathion with Calf Thymus DNA and a Synthetic DNA Duplex

1995 ◽  
Vol 50 (11-12) ◽  
pp. 820-823 ◽  
Author(s):  
Janusz Blasiak ◽  
Vladimír Kleinwächter ◽  
Zofia Walter ◽  
Renata Žaludová
Keyword(s):  
Cd Spectroscopy ◽  
Organophosphorus Insecticide ◽  
Calf Thymus Dna ◽  
Molar Ratio ◽  
Cd Spectra ◽  
Transition Range ◽  
Synthetic Dna ◽  
Negative Band ◽  
Calf Thymus ◽  
Ct Dna

Abstract The interaction of an organophosphorus insecticide methylparathion (O.O-dimethyl 0-4-nitrophenyl phosphorothioate) with double-stranded DNA was characterized by UV and circular dichroism (CD) spectroscopy. Two kinds of DNA were employed: calf thymus DNA (CT DNA) and a synthetic two-stranded oligomer of sequence 5′-d(TTGGATCCGAATT-CAAGCTT)-3′ Melting curves and CD spectra were taken for the DNAs in the presence of the insecticide at methylparathion/DNA base pair molar ratio of 0.5. The insecticide evoked a decrease of the melting temperature and a broadening of the transition range for CT DNA. Similar effects were observed for the synthetic oligomer but they were less pronounced than in the case of CT DNA. Methylparathion evoked a slight shift and an increase in the amplitude of the negative band in the CD spectra of both DNAs. Obtained results indicate that methylparathion may perturb the thermal stability and conformation of DNA, which is an evidence that the insecticide has an ability to interact directly with DNA.

scholarly journals Effects of Polycyclic Aromatic Hydrocarbon Pendant-Armed Ligands on the Catecholase Activity of Dinuclear Copper(II) Complexes

2021 ◽  
Author(s):  
Marcos da Silva ◽  
Renata Heying ◽  
Letícia da Silva ◽  
Adailton Bortoluzzi ◽  
Rosely Peralta ◽  
...  
Keyword(s):  
Deoxyribonucleic Acid ◽  
Catechol Oxidase ◽  
X Ray ◽  
X Ray Crystallography ◽  
Ph Values ◽  
Biomimetic Catalyst ◽  
Calf Thymus ◽  
Polycyclic Aromatic ◽  
Ct Dna ◽  
Potential Use

Herein, we present three new binuclear copper(II) complexes containing different polycyclic aromatic hydrocarbons, able to catalyze the oxidation of 3,5-di-tert-butylcathecol, a model substrate for catechol oxidase. The ligands and complexes were successful characterized in solid and solution states. The structure of C1 was determined by X-ray crystallography and it contains a [CuII2(L1-μ-phenoxo)(OAc)(H2O)2] unit, with two coppers in a pyramidal square geometry and a large distance of 3.715 Å between the copper(II) centers. All complexes (C1, C2 and C3) were found to be effective catalysts in the oxidation of 3,5-di-tert-butylcathecol to its quinone and C1 provided the highest catalytic constants at the three pH values studied. In addition to their potential use as a biomimetic catalyst in catechol oxidation, the interaction of these complexes with deoxyribonucleic acid from calf thymus (CT-DNA) was also studied, and C3 showed the greatest affinity with nucleic acids.

Binding of anti-inflammatory drug indomethacin with cyclodextrin and DNA: solubility, spectroscopic, and voltammetric studies

2001 ◽  
Vol 79 (10) ◽  
pp. 1431-1438 ◽  
Author(s):  
I S Shehatta ◽  
M S Ibrahim
Keyword(s):  
Hydrophobic Interactions ◽  
Double Helix ◽  
Electrochemical Behaviour ◽  
Binding Constants ◽  
Base Pairs ◽  
Inflammatory Drug ◽  
Voltammetric Studies ◽  
Anti Inflammatory ◽  
Dna Double Helix ◽  
Ct Dna

The interaction of the anti-inflammatory drug indomethacin (IMC) with α-, β-cyclodextrins (CDs) and calf thymus deoxyribonucleic acid (ct-DNA) have been investigated in the Britton-Robinson (BR) buffer (pH = 7.2) using solubility, spectroscopic, and voltammetric methods. The measurements show that the IMC molecule, acting as an intercalator, is inserted, from the p-chlorobenzoyl part, into the cavity of the cyclodextrins as well as into the base-stacking domain of the ct-DNA double helix. Upon addition of β-CD in a buffered IMC solution, the solubility of IMC increases and the Gibbs free energies of transfer of the drug from aqueous solution to the cavity of β-CD are negative and increase negatively with increasing β-CD concentration. The interaction of IMC with CDs and ct-DNA causes hypochromism and bathochromic shifts in the absorption spectra, along with pronounced changes in the electrochemical behaviour of the drug. The stoichiometry of complexes formed in solution is inferred to be 1:1. The binding constants were calculated from the increase of the solubility, the strong hypochromism, and the decrease in peak current of IMC upon the addition of the host molecules. IMC has a higher affinity for β-CD than for α-CD, as the IMC–β-CD interaction is the most exergonic. Binding is interpreted in terms of the intercalative (hydrophobic) interactions with the ct-DNA helix (i.e., the stacked base pairs) or within CD cavity.Key words: cyclodextrin, ct-DNA, anti-inflammatory drug, indomethacin, binding constant, solubility, spectra, voltammetry.

scholarly journals Thermodynamic and spectroscopic study on the binding of interaction anionic phthalocyanine with calf thymus DNA

2011 ◽  
Vol 26 (6) ◽  
pp. 357-365 ◽  
Author(s):  
Hamid Dezhampanah ◽  
Termeh Darvishzad ◽  
Mehrnaz Aghazadeh
Keyword(s):  
Ground State ◽  
Deoxyribonucleic Acid ◽  
Optical Absorption Spectra ◽  
Groove Binding ◽  
Base Pairs ◽  
Static Mode ◽  
Absorption And Fluorescence Spectroscopy ◽  
Calf Thymus ◽  
Axial Bond ◽  
Ct Dna

The interaction between anionic form of copper (II) N,N',N",N'"-tetrasulfonated phthalocyanine Cu (tspc) and to calf thymus deoxyribonucleic acid (ct-DNA) is investigated by measuring UV-vis absorption and fluorescence spectroscopy in phosphate buffer. The binding constant and stoichiometry were determined by analysis of optical absorption spectra of phthalocyanine at various ct-DNA concentrations using SQUAD software. The static mode of fluorescence quenching of phthalocyanine by calf thymus deoxyribonucleic acid indicates the formation of a ground-state complex. The formation of ground-state complex is a spontaneous molecular interaction procedure in which outside groove binding through the formation of an axial bond between the base pairs of nucleotide and Cu in the central core of phthalocyanine.

scholarly journals Study of Interaction of Dextromethorphan Hydrobromide with Deoxyribonucleic Acid by Fluorescence Quenching

2016 ◽  
Vol 19 (2) ◽  
pp. 197-205
Author(s):  
Toufiq Ul Amin ◽  
Md Reazul Islam ◽  
Md Zakir Sultan ◽  
Sonia Sultana ◽  
Md Saiful Islam ◽  
...  
Keyword(s):  
Deoxyribonucleic Acid ◽  
Living Organism ◽  
Pharmaceutical Journal ◽  
Binding Mode ◽  
Spectroscopic Techniques ◽  
Calf Thymus ◽  
Different Temperatures ◽  
Binding Forces ◽  
Ct Dna ◽  
Dextromethorphan Hydrobromide

Interactions with many clinically active therapeutic agents with deoxyribonucleic acid (DNA) are well studied and it expedites deciphering the structure of DNA and to investigate the pathological implication of those molecules in a living organism. The interaction of dextromethorphan hydrobromide (DEX) with calf thymus DNA (ct DNA) was studied employing UV absorption and fluorescence spectroscopic techniques. The binding affinity of DEX to DNA was calculated at different temperatures and the stoichiometry of binding was characterized to be about 1 dextromethorphan molecule per nucleotide. Hypochromic effect was found in the absorption spectra of dextromethorphan, and its wavelength had no shift in the presence of DNA indicating external binding mode of dextromethorphan to DNA. Quenching constants 3532 L/ mol and 12446L/ mol at 298 K and 308 K respectively with correlation co-efficient of 0.974 and 0.976, using Stern-Volmer equation and the quenching mechanism was found to be dynamic. Fluorescence spectroscopic results showed the quenching of fluorescence intensity of DEX in the presence of DNA, indicating the interaction between DEX and DNA. Based on this, hydrophobic interaction were found to play the dominating role in DEX-DNA binding and those binding forces also indicate the binding site of dextromethorphan to be in the minor groove of DNA.Bangladesh Pharmaceutical Journal 19(2): 197-205, 2016

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