A METHOD FOR DETERMINING THE RELATIVE EFFECT OF LIGANDS ON A-T AND G-C BASE-PAIRS IN DNA - APPLICATIONS TO METAL-IONS, PROTONS AND 2 AMINO-ACIDS

A new method is described for the study of specific interactions of low-molecular ligands with the base pairs of DNA. This method is based on the comparative analysis of melting temperature changes in DNAs of different GC-content in the presence of low molecular weight ligands.In this paper, the method Is applied to Mn2+, NI2+, Co2+ ions, deprotonation, amino acids, β-alanine and γ-aminobutyrlc acid (γ-ABA). Differences in Tm are affected not only by the changes of relative stability of AT- and GC-pairs, but also by other factors.A theoretical analysis of the sequence specificity of low-molecular ligands on the base pairs in DNA molecules characterized by a high degree of sequence heterogeneity is also presented. © 1990 Oxford University Press.