Effect of magnesium ions and low pH on interaction of pyrimidine oligonucleotides with dsDNA: affinity modification study
Brossalina, E.; Demchenko, E.; Vlassov, V.
Nucleic Acids Symposium Series 24: 107-111
1991
ISSN/ISBN: 0261-3166 PMID: 1841265 Document Number: 385826
Pyrimidine oligonucleotides bearing 2-chloroethylamino groups bind to corresponding sequences in dsDNA in highly specific way and efficiently alkylate target guanosine residues in purine DNA strand. At acidic pH in the presence of magnesium ions, the oligonucleotides can form nonperfect complexes with partially complementary nucleotide sequences in which some nucleotide units of the oligonucleotides are looped out. Introduction of guanosine residues in pyrimidine oligonucleotides aimed to tolerating thymidines in the purine DNA strand causes a considerable local distortions of the complex structure.