Structural and kinetic aspects of chemical reactions in DNA duplexes. Information on DNA local structure obtained from chemical ligation data

• Published in: Nucleic acids research Vol. 19; no. 11; pp. 3073 - 3080
• Main Authors: DOLINNAYA, N. G, TSYTOVICH, A. V, SERGEEV, V. N, ORETSKAYA, T. S, SHABAROVA, Z. A
• Format: Journal Article
• Language: English
• Published: Oxford Oxford University Press 11.06.1991
• Subjects: Analytical, structural and metabolic biochemistry; Autoradiography; Base Sequence; Biological and medical sciences; Carbodiimides - chemistry; DNA - chemistry; Dna, deoxyribonucleoproteins; Electrophoresis, Polyacrylamide Gel; Fundamental and applied biological sciences. Psychology; Kinetics; Molecular Sequence Data; Nucleic Acid Heteroduplexes - chemistry; Nucleic acids; Molecular hybridization; Double helical structure; Molecular structure; Oligonucleotide; Kinetics; Oligodeoxyribonucleotide; Duplex; Conformation
• ISSN: 0305-1048; 1362-4962
• DOI: 10.1093/nar/19.11.3073

Chemical ligation of oligonucleotides in double-stranded helices has been considered in its structural-kinetic aspect. A study was made of (i) two series of DNA duplexes with various arrangements of reacting groups in the ligation junction induced by mispairing or by alteration of furanose structure (the replacement of dT unit with rU, aU, IU, xU, dxT ones) and of (ii) eight synthetic water-soluble carbodiimides with different substituents at N1 and N3 atoms. We assumed that some information on the local structure of modified sites in the duplex can be obtained from kinetic parameters of oligonucleotide coupling reaction. The ratio of kinetic constants k3/(k2 + k3) for productive and nonproductive decomposition of the activated phosphomonoester derivative apparently reflects the reaction site structure: for a given duplex this parameter is virtually independent of the condensing agent composition. Based on the analysis of the chemical ligation kinetics a suggestion has been made about the conformation of some modified units in the double helix.