Genetic code expansion enables plant-directed control of bacterial activity

Zhong, V.; Jones, M. A.; Cabales, A.; Gevorgyan, A.; Inckemann, R.; Johnson, A. A.; Karunadasa, S. S.; Forti, A.; Xu, S.-L.; Kunjapur, A. M.; Brophy, J. A. N.

doi:10.64898/2026.05.29.728790

bioRxiv · 10.64898/2026.05.29.728790

Genetic code expansion enables plant-directed control of bacterial activity

Zhong, V.·Jones, M. A.·Cabales, A.·Gevorgyan, A.·Inckemann, R.·Johnson, A. A.·Karunadasa, S. S.·Forti, A.·Xu, S.-L.·Kunjapur, A. M.·Brophy, J. A. N.

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Abstract

Programmable control of microbial gene expression by plant hosts could enable a new generation of precision agricultural biotechnology. Here, using O-methyl-L-tyrosine (OMY) as a model compound, we establish non-canonical amino acids (ncAAs) as a tool for plant-based control of associated microbial activity. We use genetic code expansion to engineer OMY-dependent control of protein synthesis in the soil bacterium Bacillus subtilis. Then, we engineer agronomically diverse plants, including Arabidopsis, tomato and poplar, to biosynthesize OMY. We show that plant-derived OMY can stimulate gene expression in both model and wild soil bacteria while also demonstrating that inducible and tissue-specific expression of a single biosynthetic enzyme by the plant enables on-demand control over microbial activity. This work establishes ncAAs as a tool for programming plant-microbe partnerships.

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Zhong, V., Jones, M. A., Cabales, A., Gevorgyan, A., Inckemann, R., Johnson, A. A., Karunadasa, S. S., Forti, A., Xu, S.-L., Kunjapur, A. M., Brophy, J. A. N.. 2026-05-30. Genetic code expansion enables plant-directed control of bacterial activity. https://doi.org/10.64898/2026.05.29.728790

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