Pseudomonas aeruginosa R-bodies deliver an ADP deaminase toxin

King-Roberts, D. T.; Garakani, K.; Tao, T. Y.; Lin, H.-C.; Powell, J.; Wu, T.; Lee, E. J.; Yang, T. M.; Serebriakova, M.; Price-Whelan, A.; Cornish, V. W.; Tong, L.; Dietrich, L. E.

doi:10.64898/2026.10.21.760852

bioRxiv · 10.64898/2026.10.21.760852

Pseudomonas aeruginosa R-bodies deliver an ADP deaminase toxin

King-Roberts, D. T.·Garakani, K.·Tao, T. Y.·Lin, H.-C.·Powell, J.·Wu, T.·Lee, E. J.·Yang, T. M.·Serebriakova, M.·Price-Whelan, A.·Cornish, V. W.·Tong, L.·Dietrich, L. E.

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Abstract

Diverse bacteria produce proteinaceous polymeric coils called R-bodies (refractile bodies), which extend into ~10 m-long needles in response to environmental triggers. It has been proposed that R-bodies deliver toxins intracellularly after such bacteria are ingested by eukaryotes, but intra-host extension of R-bodies has not been directly observed and these toxins remain unidentified. We use Pseudomonas aeruginosa PA14 and Dictyostelium discoideum to show that R-bodies extend within amoebae. We also identify a novel toxin, DeaR (deaminase associated with the R-body), which contributes to predation resistance and forms a near-megadalton dodecamer with ADP deaminase activity that alters purine metabolism. Our findings elucidate the molecular basis of R-body-mediated toxicity during PA14 infection and provide a paradigm for understanding the potential of cytotoxic effectors delivered by R-bodies (CEDRs) in interkingdom interactions.

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King-Roberts, D. T., Garakani, K., Tao, T. Y., Lin, H.-C., Powell, J., Wu, T., Lee, E. J., Yang, T. M., Serebriakova, M., Price-Whelan, A., Cornish, V. W., Tong, L., Dietrich, L. E.. 2026-10-22. Pseudomonas aeruginosa R-bodies deliver an ADP deaminase toxin. https://doi.org/10.64898/2026.10.21.760852

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