INTERACTION SPECIFICITY OF BENZIMIDAZOL GROUP COMPOUNDS WITH AT-CONTAINING POLYNUCLEOTIDES

The interaction between polynucleotides: poly(dA)-poly(dT), poly(dA-dT ), poly(am2dA-dT), and the AT-specific compounds of benzimidazol group has been studied. It is been shown that these compounds bind to poly( dA)-poly(dT) and poly(dA-dT) at low and high salt concentration in sol ution. Poly(am2dA-dT) interacts with AT-specific compounds only at low salt, where this polynucleotide is in a B-form, but not at high salt, when the polynucleotide converts to another conformation. Thus, the i nteraction specificity of the groove-binding ligands is influenced not only by the minor groove substituents, but the peculiarities of the s econdary structure of polynucleotides.