The influence of duplex stabilizing oligonucleotide-effector (oligonucleotide, carrying N-(2-hydroxyethyl)phenazinium residues on both ends), on selectivity of site-directed modification of E. coli 16 S rRNA (1542 nucleotides in length) under the conditions of its secondary structure stability was studied. The constant of cooperative binding of the reagent and the oligonucleotide-effector with 16 S rRNA was determined. The accuracy of modification was shown to double in the presence of 50 μM effector at 5 μM concentration of the reagent.
