Stereopure oligonucleotide phosphorothioates as human telomerase substrates

To address the role of sulfur in the telomerase-primer recognition process, we investigated the effects of substitution of natural phosphodiester linked DNA telomerase substrates with phosphorothioate group-containing counterparts. Model dodecanucleotides with either stereorandom or stereopure all-Rp/Sp inter-nucleoside phosphorothioate linkages were evaluated and the stereorandom models found to have slightly reduced affinity for the enzyme.