Debnath Ghosal @debnathghosal.bsky.social · 12/06/2026By using visual-omics, we managed to assign the molecular identity of these filaments directly from structure, without relying on sequence homology. It turned out to be a completely novel filament system, never before described in any bacteria. 1153
Debnath Ghosal @debnathghosal.bsky.social · 12/06/2026The pilins have Ig-like folds and assemble via donor-strand exchange. The filaments show some similarities to the Pap/Fim pilus systems, so we named them “Pam” filaments (remember the Melbourne “bird”?). 150
Debnath Ghosal @debnathghosal.bsky.social · 12/06/2026Phylogenetic analysis revealed that the Pam system is widespread exclusively within CPR bacteria, with no homologs identified in non-CPR lineages, indicating that Pam pili are specific to and unique within this superphylum. 120
