Biopolymers and cell. 1992. 8 (1): 23 - 35

VESELKOV A. N.. DAVIES D. B., DJIMANT L. N.

Interaction of Acridine dye With Deoxytetranucleotides of Different Base Sequence in Aqueous Solution

Summary

    Complex formation between acridine dye proflavine and self-complementa¬ry deoxytetranucleoside triphosphates 5'-d(GpCpGpC), 5'-d(CpGpCpG), 5'-d(ApCpGpT), S'-d(ApGpCpT) in aqueous solution has been considered using data of one-dimensional and two-dimensional 'H-NMR spectroscopy (500 MHz). Two-dimensional homonuclear 'H-NMR spectroscopy (2D-COSY and 2D-NOESY) was used for comlete assignments of proton signals of molecules in solutions and for qualitative analysis of the nature of interaction of proflavine with tetranucleotides. Concentration dependences of proton chemical shifts of the molecules have been analyzed. Different schemes of complex for¬mation between dye molecules and tetranucleotides have been examined taking into ac¬count various molecular associates in solutions. Analysis of relative content of different types of complexes has been made and special features of dynamic equilibrium have been revealed as a function of base sequence of tetranucleotides. Based on the obtained results a conclusion has been made about preferntial intercalation of proflavine to CG-site of tetranucleotides in duplex form. A comparative analysis of the most favourable structures of 1 : 2 complexes of dye with tetranucleotides has been made.