Unusually Broad-spectrum small-molecule sensing using a single protein scaffold

Tian, H.; Beltran, J.; George, W.; Lenert-Mondou, C.; Seder, N.; Davis, Z. I.; Swift, S. D.; Whitehead, T. A.; Girke, T.; Wheeldon, I.; Cutler, S. R.

doi:10.1101/2025.05.15.654352

bioRxiv · 10.1101/2025.05.15.654352

Unusually Broad-spectrum small-molecule sensing using a single protein scaffold

Tian, H.·Beltran, J.·George, W.·Lenert-Mondou, C.·Seder, N.·Davis, Z. I.·Swift, S. D.·Whitehead, T. A.·Girke, T.·Wheeldon, I.·Cutler, S. R.

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Abstract

Small-molecule sensing in plants is dominated by chemical-induced dimerization modules. In the abscisic acid (ABA) system, allosteric receptors recruit phosphatase effectors and achieve nM in vivo responses from {micro}M receptor-ligand interactions. This sensitivity amplification could enable ABA receptors to serve as generic scaffolds for designing small-molecule sensors. To test this, we screened collections of mutant ABA-receptors against 2,726 drugs and other ligands and identified 569 sensors for 6.7% of these ligands. The mutational patterns indicate strong selection for ligand-specific binding pockets. We used these data to develop a sensor design pipeline and isolated sensors for multiple plant natural products, 2,4,6-trinitrotoluene (TNT), and "forever" per- and polyfluoroalkyl substances (PFAS). Thus, the ABA sensor system enables design and isolation of small-molecule sensors with broad chemical scope and antibody-like simplicity.

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Tian, H., Beltran, J., George, W., Lenert-Mondou, C., Seder, N., Davis, Z. I., Swift, S. D., Whitehead, T. A., Girke, T., Wheeldon, I., Cutler, S. R.. 2025-05-15. Unusually Broad-spectrum small-molecule sensing using a single protein scaffold. https://doi.org/10.1101/2025.05.15.654352

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