A DNA-Based Biosensor Assay for the Kinetic Characterization of Ion-Dependent Aptamer Folding and Protein Binding.

ABSTRACT: Therapeutic and diagnostic nucleic acid aptamers are designed to bind tightly and specifically to their target. The combination of structural and kinetic analyses of aptamer interactions has gained increasing importance. Here, we present a fluorescence-based switchSENSE aptasensor for the detailed kinetic characterization of aptamer-analyte interaction and aptamer folding, employing the thrombin-binding aptamer (TBA) as a model system. Thrombin-binding aptamer folding into a G-quadruplex and its binding to thrombin strongly depend on the type and concentration of ions present in solution. We observed conformational changes induced by cations in real-time and determined the folding and unfolding kinetics of the aptamer. The aptamer's affinity for K+ was found to be more than one order of ma

SUBMITTER: Ponzo I 

PROVIDER: S-EPMC6718989 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature