[Complementary addressed alkylation of 16S rRNA of Escherichia coli by 2',3'-O-[4-N-methyl-N-(2-chloroethyl)-amino]benzylidene derivatives of oligodeoxyribonucleotides. V. Study of the factors affecting selectivity of modification].

We studied the effect of different factors (reagent concentration, temperature, presence of oligonucleotide-effector (3',5'-diphenazinium derivative of oligodeoxyribonucleotide) stabilizing duplex RNA.reagent) on the selectivity of the site-directed modification of 16S rRNA with 2,3'-O-[4-N-methyl-N-(2-chloroethyl)-amino]-benzylidene derivative of oligonucleotide p(dTTTGCTCCCC)rA (reagent I) under conditions of secondary structure stability. The constant of cooperative binding of the reagent and oligonucleotide-effector with 16s rRNA was determined.