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Updated: Aug 10, 2026

Detection of Bacteria Using Fluorogenic DNAzymes
Published on: May 28, 2012
Detection of small organic analytes by fluorescing molecular switches
1Freie Universität Berlin, FB Biologie, Chemie & Pharmazie, Institut für Chemie, Thielallee 63, 14195, Berlin, Germany.
Abstract:
A sensor system was developed for the determination of theophylline concentrations based on a theophylline-dependent allosteric ribozyme (Soukup, G. A.; Breaker, R. R. Proc. Natl. Acad. Sci. U.S.A. 1999, 96, 3584) in combination with an RNA substrate which is double-labeled with a fluorophore and a quencher dye. In the presence of theophylline, a hammerhead ribozyme domain is switched into an active conformation by the action of a theophylline-binding aptamer domain. Upon substrate cleavage, the quencher is removed from the vicinity of the fluorophore, causing an increased fluorescence signal. Real-time analysis of the cleavage reactions both under single and multiple turnover conditions revealed a dependence on the cleavage rate within a range from 0.01 to 2mM theophylline. The structurally similar molecule caffeine, however, had no detectable influence on the fluorescence signal.
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