Chemical Probe for Glycosidic Conformation in Telomeric DNAs

Chemical modifications are powerful tools to probe nucleic acid structure and protein-nucleic acid interactions. Nucleic acids can be modified either randomly by a variety of chemical reagents or site-specifically with synthetic base analog substitutions. We report here the use of 8-bromodeoxyguanosine (8-Br-dG) as a modification that is directly sensitive to a dihedral angle. 8-Br-dG should prove useful as a chemical probe for the conformation about glycosidic bonds in unusual nucleic acid structures.