Temperate Phages Remodel Bacterial Flagella, Boosting Gut Colonization in 5 Mice
Updated
Updated · Nature.com · May 27
Temperate Phages Remodel Bacterial Flagella, Boosting Gut Colonization in 5 Mice
4 articles · Updated · Nature.com · May 27
FRφ, a temperate prophage found in a human Enterobacter isolate, used the RNA-guided factor TldR and a phage-encoded flagellin isoform to rewire the host’s flagellar makeup.
That remodeling increased bacterial motility, reduced mammalian immune activation, and improved engraftment in the murine gut, showing a direct host-fitness benefit from the prophage.
Cryo-EM structures revealed distinct architectures for host and prophage flagellins, linking the altered filament design to the observed physiological changes.
Mouse experiments involved 5 animals per group and showed better colonization by Enterobacter carrying FRφ, while growth and biofilm formation were not significantly changed.
The study argues that TldR factors represent an RNA-guided regulatory system that evolved in parallel to CRISPR-Cas and was co-opted by phages to reshape bacterial surface structures.
How do viruses give bacteria an 'upgrade' to help them evade the human immune system?
Could a virus turn a harmless gut bacterium into a dangerous pathogen?
Temperate Phages Remodel Bacterial Flagella via RNA-Guided TldR, Boosting Motility and Immune Evasion: Implications for Microbiome Health and Therapy
Overview
A groundbreaking study published in 2026 revealed that temperate phages, which are viruses integrated into bacterial genomes, can actively remodel how bacteria express their flagella. This discovery solves a long-standing puzzle: while flagella help bacteria move and interact with their environment, they also make bacteria more visible to the immune system and vulnerable to viral attack. By changing flagellar expression, phages help bacteria balance the need for movement with the need to avoid immune detection and phage predation. This phage-driven adaptation enhances bacterial survival and reshapes our understanding of how bacteria evolve and thrive.