Synthesis and physical characterization of DNA fragments containing N4-methylcytosine and 5-methylcytosine

• Published in: Nucleic acids research Vol. 15; no. 20; pp. 8467 - 8478
• Main Authors: BUTKUS, V, KLIMASAUSKAS, S, PETRAUSKIENE, L, MANELIENE, Z, JANULAITIS, A, MINCHENKOVA, L. E, SCHYOLKINA, A. K
• Format: Journal Article
• Language: English
• Published: Oxford Oxford University Press 26-10-1987
• Subjects: 5-Methylcytosine; Analytical, structural and metabolic biochemistry; Base Sequence; Biological and medical sciences; Biotechnology; Circular Dichroism; Cytosine - analogs & derivatives; DNA - chemical synthesis; Dna, deoxyribonucleoproteins; Fundamental and applied biological sciences. Psychology; Genetic engineering; Genetic technics; Indicators and Reagents; Kinetics; Methods. Procedures. Technologies; Nucleic Acid Conformation; Nucleic Acid Denaturation; Nucleic acids; Oligodeoxyribonucleotides - chemical synthesis; Synthetic digonucleotides and genes. Sequencing; Characterization; Chemical modification; Nucleic base; DNA; Methylation; Chemical synthesis; Physical properties
• ISSN: 0305-1048; 1362-4962
• DOI: 10.1093/nar/15.20.8467

The synthesis of N4-methyl-2'-deoxycytidine and its fully protected mononucleotide, suitable for the oligonucleotide synthesis by phosphotriester method is described. A set of octanucleotides - d(CGCGCGCG), d(CG5mCGCGCG), d(CG4mCGCGCG) and dodecanucleotides - d(GGACCCGGGTCC), d(GGA5mCCCGGGTCC), d(GGA4mCCCGGGTCC) has been synthesized in a solution. Physical characterization of the oligonucleotide duplexes by means of UV and CD spectrometry provides the evidence that 4mC similarly to 5mC favours the B--greater than Z transition, although both of these methylated cytosines inhibit the B--greater than A conformational change. N4-Methylcytosine in contrast to 5-methylcytosine reduces the DNA double helix thermal stability.