Infrared spectral studies of the non regularly alternating purine-pyrimidine hexamers d(m5CGGCM5CG), d(CBr8GGCCBr8G) and d(CGCGGC)

Autor: Tam Huynh-Dinh, Jean Igolen, Eliane Taillandier, Jean-A. Taboury, Annick Popinel, S. Adam
Rok vydání: 1986
Předmět:
Zdroj: Journal of biomolecular structuredynamics. 3(5)
ISSN: 0739-1102
Popis: The oligonucleotides d(m5CGGCm5CG), d(CBr8GGCCBr8G) and d(CGCGGC) have been prepared and studied by infrared spectroscopy. The three sequences contain two GC pairs which are out of purine-pyrimidine alternation with the rest of the sequence. From the IR data of the dlm5CGGCmCG) hexamer, it is shown that all of the dG residues adopt a syn conformation. The marker IR bands for the C3′ endo syn conformation are at 1410, 1354, 1320 and 925 cm−1 whereas those for the C2′ endo and conformation at 1420, 1374 and 890 cm−1 are clearly absent. This result implies that the two adjacent guanines of the d(m5CGGCm5CG) sequence are in syn conformation. It is suggested that duplex formation occurs in d(CGCGGC) films and that all of the guanines are in syn conformation. In contrast, the central non-brominated guanine of the dlCBr8GGCCBr8G) hexamer is found in ami conformation, as expected in a Z type structure of the non-alternating region.
Databáze: OpenAIRE