Solid-phase synthesis and hybridization properties of DNA containing sulfide-linked dinucleosides

Oligodeoxyribonucleotides incorporating non-hydrolyzable dialkyl sulfide linked thymidine dimers (TsT) were synthesized chemically by the solid-phase approach. The sulfide dimer TsT was stable to degradation by snake-venom phosphodiesterase, calf spleen phosphodiesterase, Nuclease P1 and Nuclease S1. Thermal denaturation analysis indicated that the incorporation of TsT dimers into DNA weakened, but did not prevent, binding to complementary DNA and RNA over a wide range of salt concentrations (10 mM to 2 M NaCl).