Nucleic acid detection using MNAzymes

Abstract

Deoxyribozymes are promising biotechnological tools. In a recent JACS article, Mokany et al. reported on the design of multi-component deoxyribozyme (MNAzyme) sensors based on 10-23 and 8-17 DNA enzymes. The sensors can detect down to 5 pM of a specific nucleic acid. The versatility of MNAzyme platform allows the design of catalytic cascades for signal amplification. This work is a step forward to PCR-free molecular diagnostics.

Figure 1. Design of deoxyribozyme sensors for nucleic acid analysis

A: Allosterically regulated deoxyribozyme sensors (e.g. Stojanovic et al., 2003). B: Binary deoxyribozyme sensors (e.g. Kolpashchikov, 2007 and Kolpashchikov, 2008). C: One of the MNAzyme sensors reported by Mokany et al., 2009. The enzymatic core of DNAzyme 10–23 was divided between T⁸ and A⁹ , and the analyte binding arms (black sequences) were connected to T⁸ and A⁹. The presence of oligonucleotide AF-RO3 led to the formation of the catalytically active associate (right), which cleaved the fluorogenic substrate.