Biopolymers and cell. 1996; 12 (4): 38 - 48

H-NMR investigation of the self-association of non-complementary deoxytetranucleotides of different base sequences in aqueous solution

A. N. Veselkov, S. f. Baranovsky, N. V. Petrenko.S. G. Osetrov, D. A. Veselkov, L. N. Djimant, A. Tucker, H. Parkes, D. Davies

Self-associationofdeoxytetraribonucleosidetriphosphales5'-d(CGAA), S'-d(AAGC), S'-(CTGA), 5'-d(GAAG) in aqueous solution have been studied by one-dimensional and two-dimensional H-NMR spectroscopy (500 and 600 MHz). Two-dimensional homowdear PMR spectroscopy (2D-TOCSYand 2D-NOESY) was used for complete assignments of tetranucleotides proton signals. Concentration and temperature dependences of non-exchangeable proton chemical shifts have been measured. Experimental results have been analyzed using dimer model of molecules association. Equilibrium association constants, values of limiting proton chemical shifts of tetranucleotides in the monomer and dimer states, ther-modynamic parameters Aff, AS of the reaction of molecules dimerization have been determined. Compara¬tive analysis of the self-association characteristics for non-complementary deoxytetranucleotides of dif¬ferent base sequences has been made.