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bioRxiv · 10.64898/2026.04.10.717836

Structural features of E. coli Stx bacteriophage phi24B revealed with cryo-electron microscopy

Bubenchikov, M. A.·Kuznetsov, A. S.·Matuskina, D. S.·Letarov, A. V.·Sokolova, O. S.·Moiseenko, A. V.
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Abstract

Shiga toxin-converting bacteriophages play a critical role in the emergence and virulence of pathogenic Escherichia coli strains. Despite their significance, detailed structural information on these phages remains scarce. Here we present a high-resolution cryo-electron microscopy and proteomic analysis of the phi24B bacteriophage, revealing an icosahedral capsid with T=9 symmetry, decorated by a processed esterase protein (gp84) and stabilized by cementing proteins. The tail assembly comprises a dodecameric portal, two rings of adapter proteins sharing a common fold, a hexameric nozzle, six lateral tail fibers, and a flexible central needle fiber. The binding sites of the fibers are described. Comparative analysis indicates conservation of the tail structure with related podoviruses but very different peripheral features.

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Bubenchikov, M. A., Kuznetsov, A. S., Matuskina, D. S., Letarov, A. V., Sokolova, O. S., Moiseenko, A. V.. 2026-04-11. Structural features of E. coli Stx bacteriophage phi24B revealed with cryo-electron microscopy. https://doi.org/10.64898/2026.04.10.717836

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