Segmented filamentous bacteria undergo a structural transition at their adhesive tip during unicellular to filament development.

ABSTRACT: Segmented filamentous bacteria (SFB) are intestinal commensals that promote immune system development and pathogen protection through intimate attachment to the ileal epithelium. Attachment occurs via the tip of unicellular teardrop-shaped SFB, called intracellular offsprings (IOs), before outgrowth into filaments. To characterize this critical stage of the SFB life cycle, we imaged SFB using cryo-electron microscopy and tomography. IOs were surrounded by a repetitive surface (S)-layer that became replaced by disordered hair-like structures specifically at the IO tip. During outgrowth into filaments, the S-layer was exchanged for a morphologically distinct repetitive hair-like layer. The bacterial structures and morphological transition were conserved across SFB from mouse and rat origin,

SUBMITTER: Cruz AR 

PROVIDER: S-EPMC12780176 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature