The thermal stability of a new polynucleotide complex has been used to establish the hydrogen-bonding structure of three-stranded C-G-CH+ helices. In the Hoogsteen structure, the 8NH2 group of 8NH2GMP can form a third hydrogen bond to the CH+ strand, but in the alternative structure, the 8NHz group
Effect of O(2′)-methylation on the stability of polynucleotide helices
✍ Scribed by N. Yathindra; M. Sundaralingam
- Publisher
- Wiley (John Wiley & Sons)
- Year
- 1979
- Tongue
- English
- Weight
- 551 KB
- Volume
- 18
- Category
- Article
- ISSN
- 0006-3525
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✦ Synopsis
Abstract
The effect of ribose(O2′)‐methylation on the stability of (O2′)‐methylated polyribonucleotide helices has been studied by conformational energy calculations. The preferred orientation of the methyl group is found to further stabilize the helical phosphodiester conformation (g^−^,g^−^) due to the enhanced short‐range interactions arising between the methyl groups and the adjacent ribose moieties. The experimentally observed increase in melting temperature of (O2′)‐alkylated polyribonucleotides is thus attributable to the enhanced stability of the helical backbone conformation.
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