Biophysical and biochemical investigation on the binding of a manganese–cyanonitrosyl complex with DNA

Abstract

The interaction of a cyanonitrosyl-manganate complex with DNA has been studied by u.v.-vis spectroscopy, circular dichroism, fluorescence and gel electrophoresis techniques. As the DNA 260 nm band remained insensitive to interaction, the interaction ratio was determined by monitoring the CN ) fi Mn LMCT band observed at 222 nm, and the interaction ratio was found to be in the complex (D): DNA (P) ¼ 1:0.30 from the spectrophotometric titration. The above-mentioned physical measurements indicate that the binding mode is not intercalative and the cyanonitrosyl system is a groove binder.

Insights into the in vitro Anticancer Effects of Diruthenium‐1

“…It is speculated that the efficacy of anticancer drugs in cancer cells depends mostly on their binding mode to DNA . The interaction with DNA is a very important mechanism of the cytostatic and antiproliferative activity of organometallic compounds and complexes with anticancer activity, and has long been the subject of intense study for biotechnology and medical application, still representing the main target in the development of new anticancer drugs …”

“…[83,84] The interaction with DNA is av ery important mechanism of the cytostatic and antiproliferativea ctivity of organo-metallicc ompounds and complexes with anticancer activity, and hasl ong been the subject of intense study for biotechnology and medical application,s till representing the main target in the development of new anticancer drugs. [85,86] Most organometallic compounds interactw ith DNA through three different modes of noncovalenti nteraction:i ntercalative association (sliding of ap lanar,a romatic moiety between the DNA base pairs);D NA groove binding through hydrophobic, electrostatic, and hydrogen bonding interactionso rt heir combination;o re xternal binding by electrostatic attraction and the selectivity towardap articularD NA base pair or DNA sequence. [63,77,[87][88][89][90] Metal complexes, especially those possessing planara romatic ligands, can intercalate between the DNA bases by noncovalent interactions, which can twist or even break the double helix and hence strongly influence the properties of DNA.…”

Evaluation of the interactions of DNA with the textile dyes Disperse Orange 1 and Disperse Red 1 and their electrolysis products using an electrochemical biosensor

“…Spectrum alterations reflect corresponding changes in DNA conformation and structure after interaction with other molecules [58]. Hypochromism can result from damage of the double helix structure of the DNA, leading to conformational changes [59,60]. An intercalative mode involving a strong stacking interaction between aromatic rings of molecules and the base pairs of DNA also leads to hypochromism [61].…”

Synthesis, characterization and comparative DNA interaction studies of new copper(II) and nickel(II) complexes containing mesalamine drug using molecular modeling and multispectroscopic methods

“…On the other hand, the coupling π orbital is partially filled by electrons, thus decreasing the transition probabilities and concomitantly resulting in hypochromism [26]. In general, hyperchromism and hypochromism concern the double helix structure of DNA; hyperchromism means the breakage of the secondary structure of DNA [27] and hypochromism results from the contraction of DNA in the helix axis, as well as from the conformational change of DNA [28]. The experiment was carried out for a fixed concentration of free 5-ASA (5×10 -5 M) with increasing concentrations of ct-DNA (0 to 9.1×10 -4 M) (figure 3A).…”