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Updated: Aug 11, 2026

Sequence-specific Labeling of Nucleic Acids and Proteins with Methyltransferases and Cofactor Analogues
Published on: November 22, 2014
Enhancement of the binding ability of a ligand for nucleobase recognition by introducing a methyl group
Qing Dai1, Chun-Yan Xu, Yusuke Sato
1Department of Chemistry, Graduate School of Science, Tohoku University, Japan.
Abstract:
The recognition ability of pteridine derivatives for nucleobases opposite an abasic (AP) site in an oligodeoxynucleotide (ODN) duplex is enhanced by using a propylene residue (Spacer-C3) as an AP site. The recognition ability is further enhanced both by attaching methyl groups to a fluorescent ligand and by measuring the fluorescence response at 5 degrees C; 6.2 x 10(6) M(-1) of the binding constant is attained between 2-amino-6,7-dimethyl-4-hydroxypteridine and guanine opposite the AP site in water.
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