FIG 1.

BamE plays a specific nonredundant role in the Bam complex required for the RcsF/OMP assembly. ΔbamE and not bamA101 (A) or bamB::Kan (B) mutations result in the significant decrease of RcsF/OMP cross-linking. ΔrcsF improves OMP assembly in the corresponding double mutants (A and B, lower panels). Strains were grown in glucose minimal medium at 30°C, subjected to formaldehyde cross-linking, and analyzed by immunoblotting using anti-RcsF and anti-BamA antibodies. Immunoblot analysis of the total OMPs and σ70 (loading control) levels was performed on the total cell extracts (without cross-linking). Plate growth phenotype of bamA101 ΔbamE (C) and ΔbamE bamB::Kan (D) double mutants and their ΔrcsF derivatives. Strains were streaked on indicated agar plates; plates were incubated at 30°C or 37°C. Growth was assayed after 48 h.