Interaction between 3-(p-tolylamino)-1,5-azulenequinone and the deoxyguanosine residue in various oligonucleotides upon photolysis.
Eight single-stranded oligodeoxyribonucleotides 32P-labeled at the 5'-end were synthesized; they were annealed with the complementary oligodeoxyribonucleotides to form the corresponding double-stranded helices. These duplexes possessed standard Watson-Crick base pairs, locally perturbed sites of a base mismatch, or a bulge. Further, 5'-32P-labeled oligodeoxyribonucleotides with a hairpin loop were also synthesized. Cleavage of these single- and double-stranded oligodexyribonucleotides selectively at the deoxyguanosine residue was accomplished by use of 3-(p-tolylamino)-1,5-azulenequinone 1 upon irradiation with 350 nm UV light. The single strands were cleaved more efficiently than the double-helices. For the helices containing a deoxyguanosine residue at a bulge, at a hairpin loop or toward the end, the cleaving efficiency was increased. Computation results indicate that two possibilities exist for agent 1 to form two "Watson-Crick type" hydrogen bonds with guanine in single-stranded oligodeoxyribonucleotides; yet, only one possibility exists in duplexes.
Hwu
J R
JR
Institute of Chemistry, Academia Sinica, Taipei, Taiwan 11529, ROC. jrhwu@chem.sinica.edu.tw
Tsai
F Y
FY
Tsay
S C
SC
Chuang
S H
SH
Su
T R
TR
Lin
S B
SB
Lin
W C
WC
Hsieh
C L
CL
Kan
L S
LS
D001483:Base Sequence; D003849:Deoxyguanosine / Q000737:chemistry*; D004591:Electrophoresis, Polyacrylamide Gel; D008958:Models, Molecular; D009690:Nucleic Acid Conformation; D009838:Oligodeoxyribonucleotides / Q000737:chemistry* / Q000528:radiation effects; D010782:Photolysis; D013816:Thermodynamics
D009838:Oligodeoxyribonucleotides; D003849:Deoxyguanosine