To monitor protein-drug interactions (PDIs) in vitro is essential for the drug discovery processes including drug screening, structure-activity-relationship (SAR), and mode-of-action (MOA) studies 1, 2. The therapeutic efficacy of drugs is mediated by physical interaction with their cognate targets (mainly proteins). Taken together, our results present the YaxAB nanopore as a robust platform for label-free, ultrasensitive, single-molecule detection of PDIs, opening up a possibility for low-cost, highly efficient drug discovery against diverse drug targets.Ĭurrent drug development suffers from high cost and low efficiency of the drug discovery process. Distinctive nanopore event distributions observed in the two-dimensional (ΔI/I o-versus-I N) plot illustrate the ability of the YaxAB nanopore to discriminate individual small-molecule drugs bound to Bcl-xL from non-binders. The long funnel-shaped structure and nanofluidic characteristics of the YaxAB nanopore enable the electro-osmotic trapping of diverse folded proteins and high-resolution monitoring of PDIs.

Using this YaxAB nanopore, we demonstrate label-free, single-molecule detection of interactions between the anticancer Bcl-xL protein and small-molecule drugs as well as the Bak-BH3 peptide. Here, we develop a biological nanopore sensor for single-molecule detection of proteins and PDIs using the pore-forming toxin YaxAB. In drug discovery, efficient screening of protein-drug interactions (PDIs) is hampered by the limitations of current biophysical approaches.

Graphpad 9