Structural highlights
Publication Abstract from PubMed
The incorporation of the bicyclic cytosine analogue 7,8-dihydropyrido[2,3-d]pyrimidin-2-one (X) into DNA duplexes results in a significant enhancement of their stability (3-4 K per modification). To establish the effects of X on the local hydrogen-bonding and base stacking interactions and the overall DNA conformation, and to obtain insights into the correlation between the structure and stability of X-containing DNA duplexes, the crystal structures of [d(CGCGAATT-X-GCG)](2) and [d(CGCGAAT-X-CGCG)](2) have been determined at 1.9-2.9 A resolutions. In all of the structures, the analogue X base pairs with the purine bases on the opposite strands through Watson-Crick and/or wobble type hydrogen bonds. The additional ring of the X base is stacked on the thymine bases at the 5'-side and overall exhibits greatly enhanced stacking interactions suggesting that this is a major contribution to duplex stabilization.
Insights into the DNA stabilizing contributions of a bicyclic cytosine analogue: crystal structures of DNA duplexes containing 7,8-dihydropyrido [2,3-d]pyrimidin-2-one.,Magat Juan EC, Shimizu S, Ma X, Kurose T, Haraguchi T, Zhang F, Tsunoda M, Ohkubo A, Sekine M, Shibata T, Millington CL, Williams DM, Takenaka A Nucleic Acids Res. 2010 Jun 16. PMID:20554855[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Magat Juan EC, Shimizu S, Ma X, Kurose T, Haraguchi T, Zhang F, Tsunoda M, Ohkubo A, Sekine M, Shibata T, Millington CL, Williams DM, Takenaka A. Insights into the DNA stabilizing contributions of a bicyclic cytosine analogue: crystal structures of DNA duplexes containing 7,8-dihydropyrido [2,3-d]pyrimidin-2-one. Nucleic Acids Res. 2010 Jun 16. PMID:20554855 doi:10.1093/nar/gkq519