Phage-Inducible Chromosomal Jumbo Islands (PICJIs) spreading antimicrobial resistance, host-adaptation factors and defense systems, a novel satellite family of nucleus-forming Chimalliviridae

Rossignol, A.; Praud, K.; Alexandre, M. R.; Mikhayel, M.; Foubert, I.; Raynal, P.-I.; Fabre, L.; Leclercq, S. O.; Weill, F.-X.; Sarkis, D. K.; Doublet, B.

doi:10.64898/2026.11.03.763896

bioRxiv · 10.64898/2026.11.03.763896

Phage-Inducible Chromosomal Jumbo Islands (PICJIs) spreading antimicrobial resistance, host-adaptation factors and defense systems, a novel satellite family of nucleus-forming Chimalliviridae

Rossignol, A.·Praud, K.·Alexandre, M. R.·Mikhayel, M.·Foubert, I.·Raynal, P.-I.·Fabre, L.·Leclercq, S. O.·Weill, F.-X.·Sarkis, D. K.·Doublet, B.

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Abstract

Phage satellites are mobile genetic elements that depend on helper bacteriophages to promote their own dissemination. Here, we identified a novel family of large satellites, named Phage-Inducible Chromosomal Jumbo Islands (PICJIs), that are widespread in Escherichia coli and Salmonella enterica among diverse hosts, worldwide. These largest satellites to date (71.6 {+/-} 15.8 kbp) are specifically transduced by the persistent jumbo bacteriophage Goslarvirus of the nucleus-forming Chimalliviridae family. Furthermore, PICJIs carried numerous accessory genes associated with clinically relevant antimicrobial resistances, host-adaptation, and several anti-phage defense systems.

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Rossignol, A., Praud, K., Alexandre, M. R., Mikhayel, M., Foubert, I., Raynal, P.-I., Fabre, L., Leclercq, S. O., Weill, F.-X., Sarkis, D. K., Doublet, B.. 2026-11-04. Phage-Inducible Chromosomal Jumbo Islands (PICJIs) spreading antimicrobial resistance, host-adaptation factors and defense systems, a novel satellite family of nucleus-forming Chimalliviridae. https://doi.org/10.64898/2026.11.03.763896

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