Synthesis and physical characterization of DNA fragments containing N4-methylcytosine and 5-methylcytosine.
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.
Butkus
V
V
ESP Fermentas, All Union Research Institute of Applied Enzymology, Vilnius Lithuanian SSR.
Klimasauskas
S
S
Petrauskiene
L
L
Maneliene
Z
Z
Janulaitis
A
A
Minchenkova
L E
LE
Schyolkina
A K
AK
D044503:5-Methylcytosine; D001483:Base Sequence; D002942:Circular Dichroism; D003596:Cytosine / Q000031:analogs & derivatives*; D004247:DNA / Q000138:chemical synthesis*; D007202:Indicators and Reagents; D007700:Kinetics; D009690:Nucleic Acid Conformation; D009691:Nucleic Acid Denaturation; D009838:Oligodeoxyribonucleotides / Q000138:chemical synthesis*
D007202:Indicators and Reagents; D009838:Oligodeoxyribonucleotides; C039052:N(4)-methylcytosine; D044503:5-Methylcytosine; D003596:Cytosine; D004247:DNA