A novel replicating circular DNAzyme.

Fei Chen; Ruijian Wang; Zhe Li; Bin Liu; Xiaoping Wang; Yanhong Sun; Dongyun Hao; Jin Zhang

doi:10.1093/nar/gkh547

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PubMed · 15115797

A novel replicating circular DNAzyme.

Fei Chen·Ruijian Wang·Zhe Li·Bin Liu·Xiaoping Wang·Yanhong Sun·Dongyun Hao·Jin Zhang

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Abstract

10-23 DNAzyme has the potential to suppress gene expressions through sequence-specific mRNA cleavage. However, the dependence on exogenous delivery limits its applications. The objective of this work is to establish a replicating DNAzyme in bacteria using a single-stranded DNA vector. By cloning the 10-23 DNAzyme into the M13mp18 vector, we constructed two circular DNAzymes, C-Dz7 and C-Dz482, targeting the beta-lactamase mRNA. These circular DNAzymes showed in vitro catalytic efficiencies (kcat/K(M)) of 7.82 x 10(6) and 1.36 x 10(7) M(-1) x min(-1), respectively. Their dependence on divalent metal ions is similar to that found with linear 10-23 DNAzyme. Importantly, the circular DNAzymes were not only capable of replicating in bacteria but also exhibited high activities in inhibiting beta-lactamase and bacterial growth. This study thus provides a novel strategy to produce replicating DNAzymes which may find widespread applications.

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Base Sequence Catalysis Cations, Divalent DNA, Catalytic DNA, Circular Escherichia coli Genetic Engineering Genetic Vectors Magnesium beta-Lactamases Journal Article Research Support, Non-U.S. Gov't

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Fei Chen, Ruijian Wang, Zhe Li, Bin Liu, Xiaoping Wang, Yanhong Sun, Dongyun Hao, Jin Zhang. 2004-04-28. A novel replicating circular DNAzyme.. https://doi.org/10.1093/nar%2Fgkh547

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