Hiroshi Sugiyama

Ab initio molecular orbital calculations of stacked DNA bases were performed at the 3-21G(*) and 6-31G* levels to elucidate the origin of the 5‘-GG-3‘ sequence specificity for the photocleavage of DNA in the presence of electron-accepting photosensitizers. Ionization potentials (IP) were estimated as Koopman's theorem values for 16 sets of two stacked nucleobases and seven sets of stacked nucleobase pair systems in a B-form geometry. It was found that the GG/CC system is the lowest among the 10

A G-quadruplex (G4) is a well-known nucleic acid secondary structure comprising guanine-rich sequences, and has profound implications for various pharmacological and biological events, including cancers. Therefore, ligands interacting with G4s have attracted great attention as potential anticancer therapies or in molecular probe applications. To date, a large variety of DNA/RNA G4 ligands have been developed by a number of laboratories. As protein-targeting drugs face similar situations, G-quadr

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTHighly sequence-selective photoreaction of 5-bromouracil-containing deoxyhexanucleotidesHiroshi Sugiyama, Yasushi Tsutsumi, and Isao SaitoCite this: J. Am. Chem. Soc. 1990, 112, 18, 6720–6721Publication Date (Print):August 1, 1990Publication History Published online1 May 2002Published inissue 1 August 1990https://pubs.acs.org/doi/10.1021/ja00174a046https://doi.org/10.1021/ja00174a046research-articleACS PublicationsRequest reuse permissionsArticle Views

Intramolecular folding in three tandem guanine repeats of human telomeric DNA has been investigated using optical-tweezers, MD simulation and circular dichroism. A mechanically and thermodynamically stable species in this sequence shows a structure consistent with a triplex conformation. A similar species has also been observed to coexist with a G-quadruplex in a DNA sequence with four tandem guanine repeats.