5′-Peptidyl substituents allow a tuning of the affinity of oligodeoxyribonucleotides for RNA

The affinity of amide-linked 5′-aminoacyl and 5′-dipeptidyl DNA octamers for two RNA undecamers with 3′-overhangs was measured via UV melting analysis. A sequence-dependent increase in melting points was observed. At low ionic strength, two appended lysine residues elevate melting points more than two additional A:U base pairs.