Small-Molecule Screening Made Simple for a Difficult Target with a Signaling Nucleic Acid Aptamer that Reports on Deaminase Activity

摘要

Conventional approaches to small-molecule screening are currently being challenged by the availability of vast amounts of genomic sequence information and a plethora of potential targets. This challenge has precipitated a need for new screening paradigms that emphasize simplicity, capacity, and parallelization. Herein we report the application of signaling DNA-aptamer technology for the development and execution of a high-throughput screen for an otherwise problematic target, adenosine deaminase (ADA). The approach employed a signaling DNA aptamer that reports on adenosine concentration over the course of the enzymatic reaction. The assay was extremely robust in a screen of more than 44 000 molecules and revealed a new competitive inhibitor of the deaminase. Nucleic acid aptamers have proven worthy as a routinely selectable species for a wide variety of small molecules and so this proof-of-principle work has broad applicability and potential for the development of enzymatic assays suitable for a chemical genomic approaches.