in the present work, the interaction of three water soluble porphyrins, tetra (p-trimethyle) ammoniumphenyl porphyrin iodide (tapp) as a cationic porphyrin, tetra sodium meso-tetrakis (p-sulphonatophenyle) porphyrin (tspp) as an anionic porphyrin and manganese tetrakis (p-sulphonato phenyl)porphinato acetate (mntspp) as a metal porphyrin, with dna have been studied by isothermaltitration microc...

The main calorimetric principles used in isothermal microcalorimetry are briefly discussed. Different chemical calibration and test reactions are discussed, with a focus on reactions suitable for ambient conditions: reactions initiated by mixing of liquids (including titration microcalorimetry), dissolution of solid compounds and of slightly soluble gases, a photochemical process, and thermal p...

Kinetic and thermodynamic studies have been made on the effect of the inosine product on the activity of adenosine deaminase in a 50 mM sodium phosphate buffer, pH 7.5, at 27 degrees C using UV spectrophotometry and isothermal titration calorimetry (ITC). A competitive inhibition was observed for inosine as a product of the enzymatic reaction. A graphical-fitting method was used for determinati...

Kinetic and thermodynamic studies were made on the effect of caffeine on the activity of adenosine deaminase in 50 mM sodium phosphate buffer, pH 7.5, using UV spectrophotometry and isothermal titration calorimetry (ITC). An uncompetitive inhibition was observed for caffeine. A graphical fitting method was used for determination of binding constant and enthalpy of inhibitor binding by using iso...

The binding constants between Ni2+ and Helicobacterpylori NikR have been determined using isothermal titration microcalorimetry in order to rationalize the role of this protein as a nickel-dependent biological sensor.

The capabilities of contemporary differential scanning and isothermal titration microcalorimetry for studying the thermodynamics of protein unfolding/refolding and their association with partners, particularly target DNA duplexes, are considered. It is shown that the predenaturational changes of proteins must not be ignored in studying the thermodynamics of formation of their native structure a...

The interaction of chitosan with plasmid DNA was investigated as a function of pH, buffer composition, degree of deacetylation (DDA), and molecular weight (M(n)) of chitosan, using isothermal titration microcalorimetry (ITC). The Single Set of Identical Sites model was used to obtain the enthalpy of interaction, the binding constant, and the stoichiometry of binding. The chitosan-DNA interactio...