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Title: RE-SELEX: restriction enzyme-based evolution of structure-switching aptamer biosensors
Aptamers are widely employed as recognition elements in small molecule biosensors due to their ability to recognize small molecule targets with high affinity and selectivity. Structure-switching aptamers are particularly promising for biosensing applications because target-induced conformational change can be directly linked to a functional output. However, traditional evolution methods do not select for the significant conformational change needed to create structure-switching biosensors. Modified selection methods have been described to select for structure-switching architectures, but these remain limited by the need for immobilization. Herein we describe the first homogenous, structure-switching aptamer selection that directly reports on biosensor capacity for the target. We exploit the activity of restriction enzymes to isolate aptamer candidates that undergo target-induced displacement of a short complementary strand. As an initial demonstration of the utility of this approach, we performed selection against kanamycin A. Four enriched candidate sequences were successfully characterized as structure-switching biosensors for detection of kanamycin A. Optimization of biosensor conditions afforded facile detection of kanamycin A (90 μM to 10 mM) with high selectivity over three other aminoglycosides. This research demonstrates a general method to directly select for structure-switching biosensors and can be applied to a broad range of small-molecule targets.  more » « less
Award ID(s):
1904885
NSF-PAR ID:
10355111
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Chemical Science
Volume:
12
Issue:
35
ISSN:
2041-6520
Page Range / eLocation ID:
11692 to 11702
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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