A DNAzyme Feedback Amplification Strategy for Biosensing

Meng Liu; Qiang Zhang; Dingran Chang; Jimmy Gu; John D Brennan; Yingfu Li

doi:10.1002/anie.201700054

A DNAzyme Feedback Amplification Strategy for Biosensing

Angew Chem Int Ed Engl. 2017 May 22;56(22):6142-6146. doi: 10.1002/anie.201700054. Epub 2017 Mar 28.

Authors

Meng Liu^{1

2}, Qiang Zhang², Dingran Chang¹, Jimmy Gu¹, John D Brennan², Yingfu Li^{1

2}

Affiliations

¹ Department of Biochemistry and Biomedical Sciences and Chemistry & Chemical Biology, McMaster University, 1280 Main Street West, Hamilton, ON, L8S 4K1, Canada.
² Biointerfaces Institute, McMaster University, 1280 Main Street West, Hamilton, ON, L8S 4L8, Canada.

PMID: 28370773
DOI: 10.1002/anie.201700054

Abstract

We report a signal amplification strategy termed DNAzyme feedback amplification (DFA) that takes advantage of rolling-circle amplification (RCA) and an RNA-cleaving DNAzyme (RCD). DFA employs two specially programmed DNA complexes, one composed of a primer and a circular template containing the antisense sequence of an RCD, and the other composed of the same circular template and an RNA-containing substrate for the RCD. RCA is initiated at the first complex to produce RCD elements that go on to cleave the substrate in the second complex. This cleavage event triggers the production of more input complexes for RCA. This reaction circuit continues autonomously, resulting in exponential DNA amplification. We demonstrate the versatility of this approach for biosensing through the design of DFA systems capable of detecting a microRNA sequence and a bacterium, with sensitivity improvements of 3-6 orders of magnitude over conventional methods.

Keywords: DNAzymes; RNA cleavage; biosensors; feedback amplification; rolling-circle amplification.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Biosensing Techniques / methods*
DNA, Catalytic / metabolism*
Nucleic Acid Amplification Techniques / methods*
RNA Cleavage

Substances

DNA, Catalytic