8-cyclopropyl-2'-deoxyguanosine: a hole trap for DNA-mediated charge transport.
DNA duplexes containing 8-cyclopropyl-2'-deoxyguanosine ((8CP) G) were synthesized to investigate the effect of the C8-modified deoxyguanosine as a kinetic trap for transient hole occupancy on guanines during DNA-mediated hole transport (HT). Thermal denaturation and CD spectra show that DNA duplexes containing (8CP) G are able to form stable B-form duplexes. Photoirradiation of terminal tethered anthraquinone can induce oxidative decomposition of (8CP) G through DNA HT along adenine tracts with lengths of up to 4.8 nm. Shallow and periodic distance dependence was observed in a long adenine tract with intervening guanines. The efficient charge transport indicates that (8CP) G can electronically couple well with a DNA bridge and form HT-active conformational domains to facilitate transient hole delocalization over an adenine tract.
Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371 (Singapore).
Jiun Ru
JR
Wong
Fangwei
F
Shao
D002412:Cations / Q000378:metabolism; D004247:DNA / Q000737:chemistry* / Q000378:metabolism; D003849:Deoxyguanosine / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry; D007700:Kinetics; D010084:Oxidation-Reduction
D002412:Cations; D004247:DNA; D003849:Deoxyguanosine
DNA; charge transport; hole traps; nucleosides; oxidation