Albany 2013: Book of Abstracts
June 11-15 2013
©Adenine Press (2012)
Novel Interpretation of the Isotherms of Multimodal Ligands Binding with DNA
The binding of ligands with DNA is a key moment in a whole range of cellular processes that provide not only the normal cell vital activity but also the development of some pathological processes. Depending on ligand type, structure of DNA adsorption centers and physical-chemical conditions of the surrounding, ligand may bind to DNA by several modes (Arakelyan et al. 2000). Particularly adsorption isotherm of multimodal ligands binding to DNA in Scatchard`s coordinates has a concave shape with two brightly expressed linear areas in the region of small fillings. The analysis of such type of adsorption isotherm for determining of important binding parameters such as binding constant and number of adsorption centers (the part of DNA polymer with which one ligand molecule binds) presents difficulties. Practically in all cases the analysis of such adsorption isotherm is carried out by linear parts of curves. Such analysis mode of experimental points is approximate method, since all registered of experimental points are roughly divided into two groups and they are treated by linear binding isotherm and therefore the binding parameters are determined.
In the present work the non linear adsorption isotherm in Scatchard`s coordinates is obtained which allowed provided the more precise treatment of all experimental points by unique curve which includes linear regions as well. Such mode of treatment of experimental points makes more precise the determination of not only binding constant and number of adsorption centers that correspond to the one ligand molecule binding, but also additional binding parameter – a proportion of adsorption centers of each binding to DNA type of multimodal ligand.
Arakelyan, V. B., Babayan, Yu. S. & Potikyan, G.(2000). Determination of constant rates of adsorption of ligand on DNA. J Biomol Struct Dyn 25, 119-125.
1Poghos O. Vardevanyan
Department of 1Biophysics and 2Molecular Physics