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bioRxiv · 10.64898/2026.08.27.747610

Subtyping active-site inhibitor binding mode to Abl kinase using super-resolution nanopore tweezers.

Abstract

Accurate determination of kinase inhibitor binding modes could provide essential information for understanding resistance mechanisms and accelerating drug discovery. While conventional structural methods such as X-ray crystallography, cryo-EM and NMR provide high-resolution information but are low-throughput and capture largely static snapshots of dynamic protein-ligand interactions Here, we introduce a single-molecule nanopore tweezer platform that functionally subtypes ATP-competitive Abl kinase inhibitors by resolving distinct ionic current signatures of Abl-inhibitor complexes. This approach distinguishes Type I, Type IIA, and Type IIB inhibitors without structural determination. We further show how clinically relevant Abl variants (T315I and E255V) reshape inhibitor engagement and binding modes. By combining baseline probability features with wavelet-based time-frequency descriptors, ensemble machine-learning models achieved 97.5% classification accuracy across seven kinase inhibitor binding modes at sub-angstrom resolution and enabled deconvolution of mixed-inhibitor samples at nanomolar concentrations. These results establish nanopore tweezers as a label-free, super-resolution platform for profiling kinase conformational states and inhibitor binding modes, complementing structural approaches and supporting precision oncology.

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Ly, N., Wang, Y.-H., Foster, J., DeCoeur, D., Nguyen, L., Wu, B., Milenkovic, O., Chen, M.. 2026-08-29. Subtyping active-site inhibitor binding mode to Abl kinase using super-resolution nanopore tweezers.. https://doi.org/10.64898/2026.08.27.747610

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