Extended Data Fig. 4: Phenotypic characterisation of strains with deletions in BAM_FJ subunits or BAM_FJ subunit homologues.

a, Results of attempts to delete Bam_FJ subunits and their homologues in different genetic backgrounds. Mutations and their combinations that were viable are indicated by green dots, while those that could not be constructed are indicated by red dots and are assumed to disrupt essential cell functions. b, Immunoblots of whole cells and isolated membranes of strains containing in-frame deletions of bamM or bamP. The cytoplasmic protein GroEL and OM protein OmpA were used as loading controls. *, non-specific band. Similar results were obtained from 3 biological repeats. c, Growth curves on rich CYE medium. Shown are the means ± 1 SD from three biological repeats. d, Growth curves on minimal medium containing either galactomannan or xyloglucan as carbon source. Shown are the means ± 1 SD from three biological repeats. e, Spreading (gliding) morphology of colonies on agar. Scale bar, 5 mm. Similar data were obtained for three biological repeats. f,g, OM integrity assays. Cells were grown on CYE agar with the indicated additions. wt, wild type; ΔbamP-P3, strain deleted for BamP, BamP2, and BamP3; ΔbamP-P4, strain deleted for all BamP homologues (ΔbamP-P3 ΔbamP4). The ΔporV Δplug background permeabilizes the OM through opening the T9SS translocon channel¹⁵. Similar data were obtained for three biological repeats. h, BamP overproduction restores vancomycin resistance to a strain lacking all BamP homologues (strain ΔbamP-P4). Where indicated strains were transformed with plasmids overproducing N-terminally Twin-Strep-tagged BamP (p^TSBamP) or BamP4 (p^TSBamP4). wt, wild type. Similar data were obtained for three biological repeats.