Biopolymers and cell. 1989. Volume 5. № 1. 22 - 27
V. V. Zinoviev, N. I. Rechkunova, Yu. A. Corbunov, Ya. I. Buryanov, E. G. Malygin
THE SIGNIFICANCE OF INTERNUCLEOTIDE PHOSPHATES AND NONCOMPLEMENTARY SUBSTITUTIONS IN THE OLIGONUCLEOTIDE SUBSTRATES ON THE INTERACTION WITH THE DNA METHYLASE Ecodam
Summary
Eco dam methylase is investigated for its interaction with different synthetic oligonucleotide substrates containing some defects in the GATC sequence. The defects are as follows: the absence of one or several nucleotide residues, the presence of 3'-phosphate residue with CHa-S-group, noncomplementary substitution of Ade by Gua or of Gua for Ade in the recognition site of methylase Eco dam. The presence of the 3'S-methyl thiophosphate residue has no essential effect on the methylation of oligonucleotide complexes as compared to the analogous complexes lacking internucleotide phosphate. The introduction of the noncomplementary base pair in the recognition site results in the loss of substrate properties of such imperfect duplexes.