A Highly Specific DNA Aptamer for RNase H2 from .

Molecular recognition elements with high specificity are of great importance for the study of molecular interactions, accurate diagnostics, drug design, and personalized medicine. Herein, a highly specific DNA aptamer for RNase H2 from () was generated by SELEX and minimized to 40 nucleotides. The aptamer exhibits a dissociation constant () of 1.8 ± 0.5 nM and an inhibition constant (IC) of 7.1 ± 0.6 nM for RNase H2, both of which are 2 orders of magnitude better for the same enzyme from other control bacteria. The fluorescent version of the aptamer can distinguish from several other control bacteria in a cell lysate assay. This work demonstrates that a ubiquitous protein like RNase H2 can still be used as the target for the development of highly specific aptamers and the combination of the protein and the aptamer can achieve the recognition specificity needed for a diagnostic test and drug development.