title: Photoinduced changes in hydrogen bonding patterns of 8-thiopurine nucleobase analogues in a DNA strand.
abstract: Hydrogen bonds (H-bonds) formed between nucleobases play an important role in the construction of various nucleic acid structures. The H-donor and H-acceptor pattern of a nucleobase is responsible for selective and correct base pair formation. Herein, we describe an 8-thioadenine nucleobase analogue and an 8-thiohypoxanthine nucleobase analogue with a photolabile 6-nitroveratryl (NV) group on the sulfur atom (SA(NV) and SH(NV), respectively). Light-triggered removal of the NV group causes tautomerization and a change in the H-bonding pattern of SA(NV) and SH(NV). This change in the H-bonding pattern has a strong effect on base recognition by 8-thiopurine nucleobase analogues. In particular, base recognition by SH(NV) is clearly shifted from guanine to adenine upon photoirradiation. These results show that a photoinduced change in the H-bonding pattern is a unique strategy for manipulating nucleic acid assembly with spatiotemporal control.
authors.affiliation: Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan. obika@phs.osaka-u,ac.jp.
authors.forename: Kunihiko
authors.initials: K
authors.lastname: Morihiro
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Kodama
authors.forename: Shohei
authors.initials: S
authors.lastname: Mori
authors.forename: Satoshi
authors.initials: S
authors.lastname: Obika
mesh_terms: D001483:Base Sequence; D004247:DNA / Q000737:chemistry* / Q000235:genetics; D006860:Hydrogen Bonding; D008027:Light; D011687:Purines / Q000737:chemistry*; D044366:Transition Temperature
chemical_list: D011687:Purines; D004247:DNA