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bioRxiv · 10.1101/2025.04.29.651224

A Functional Assay For Mining Non-Inhibitory Enzyme Ligands From One Bead One Compound Libraries: Application to E3 Ubiquitin Ligases

Gui, W.·Goss, A.·Kodadek, T.
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Abstract

Chemical dimerizers are synthetic molecules that bring into proximity two or more proteins that do not normally interact with one another. A major application of this technology is to recruit an enzyme to a target protein, resulting in its post-translational modification (PTM). In particular, chemical dimerizer-mediated poly-Ubiquitylation of proteins has garnered an enormous amount of interest as a new drug modality. A fundamental requirement for the construction of new PTM-driving dimerizers is an enzyme ligand that does not inhibit its activity. Traditional activity-based high-throughput screening platforms are not suited for this purpose. Here we describe a novel platform for screening libraries of bead-displayed compounds that links a requirement for small molecule binding to the enzyme with enzyme-mediated modification of a nearby substrate. This system ensures that the enzyme-recruiting small molecules do not interfere with the catalytic function of the enzyme. We demonstrate the utility of this system in the context of E3 Ubiquitin ligase-recruiting molecules and report the discovery of a novel, low molecular mass ligand for the Von Hippel Landau (VHL) protein.

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Gui, W., Goss, A., Kodadek, T.. 2025-04-29. A Functional Assay For Mining Non-Inhibitory Enzyme Ligands From One Bead One Compound Libraries: Application to E3 Ubiquitin Ligases. https://doi.org/10.1101/2025.04.29.651224

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