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Updated: Jun 5, 2026
Sequence-specific and Selective Recognition of Double-stranded RNAs over Single-stranded RNAs by Chemically Modified Peptide Nucleic Acids
Published on: September 21, 2017
Discrimination of phosphorylated double stranded DNA by naphthalene diimide having zinc(II) dipicolylamine complexes
Sadayoshi Watanabe1, Keiichi Ohtsuka, Shinobu Sato
1Department of Applied Chemistry, Kyushu Institute of Technology, 1-1 Senesui-cho, Tobata-ku, Kitakyushu-shi, Fukuoka 804-8550, Japan.
Abstract:
Discrimination of phosphomonoesters and phosphodiesters of DNA was attempted with naphthalene diimide carrying two zinc-dipicolylamine (Dpa) units (1). The binding constant of 1 for a self-complementary octanucleotide was 1.3×10(6)M(-1), while the value for the phosphorylated counterpart was 4.8×10(6)M(-1). This fourfold increase in the binding constant seems to stem from higher affinity of the terminal monophosphate over the phosphodiesters of DNA as the fourth ligand for the metal in 1. Likewise, the binding constant of 1 for DNase I-treated calf thymus DNA (average size 200bp) was twice as large as that for untreated DNA (1kb), possibly because the terminal phosphate groups are five times abundant in the former. These findings provide a clue to developing a system where phosphomonoesters generated upon DNA nicking are discriminated specifically from intact phosphodiesters.
