Breaking the conservation of guanine residues in the catalytic loop of 10–23 DNAzyme by position-specific nucleobase modifications for rate enhancement

10–23 DNAzyme has been used as a very good model for exploring the potential of functional nucleic acids. Its 15-mer catalytic core has been demonstrated to be the optimized in vitro selection result. However, with the introduction of protein-like functional groups through 2′-deoxyguanosine analogues, its two highly conserved guanine residues (G2 and G14) can be modified for more efficient 10–23 DNAzyme analogues. This result implies that chemical modifications of functional nucleic acids with well-designed nucleoside analogues of each canonical residue could be used as the first step in the efforts toward more powerful functions of nucleic acids.