biostudies-literatureHart EMHHS | NIH | National Institute of General Medical SciencesNIGMS NIH HHSe00662-19https://www.ebi.ac.uk/biostudies/studies/S-EPMC6529638biostudies-literatureUnknown10(3)The selective permeability of the Gram-negative outer membrane (OM) is maintained by integral β-barrel outer membrane proteins (OMPs). The heteropentomeric β-barrel assembly machine (Bam) folds and inserts OMPs into the OM. Coordination of the essential proteins BamA and BamD is critical for OMP assembly and therefore the viability of the cell. The role of the nonessential lipoproteins BamBCE has yet to be characterized; however, genetic evidence suggests that they have nonoverlapping roles in OMP assembly. In this work, we quantify changes of the proteome in the conditional lethal Δ<i>bamB</i> Δ<i>bamE</i> double mutant. We show that cells lacking BamB and BamE have a global OMP defect that is a result of a lethal obstruction of an assembly-competent Bam complex by the lipoprotein RcsF. RmBioThe Synthetic Phenotype of Δ<i>bamB</i> Δ<i>bamE</i> Double Mutants Results from a Lethal Jamming of the Bam Complex by the Lipoprotein RcsF.PMC6529638F32 GM129913R35 GM128813R01 GM034821R35-GM118024T32 GM007388R01-GM034821R35 GM118024R35-GM129913T32-GM007388Silhavy TJWuhr MGupta MHart EMfalseThe Synthetic Phenotype of Δ<i>bamB</i> Δ<i>bamE</i> Double Mutants Results from a Lethal Jamming of the Bam Complex by the Lipoprotein RcsF.The selective permeability of the Gram-negative outer membrane (OM) is maintained by integral β-barrel outer membrane proteins (OMPs). The heteropentomeric β-barrel assembly machine (Bam) folds and inserts OMPs into the OM. Coordination of the essential proteins BamA and BamD is critical for OMP assembly and therefore the viability of the cell. The role of the nonessential lipoproteins BamBCE has yet to be characterized; however, genetic evidence suggests that they have nonoverlapping roles in OMP assembly. In this work, we quantify changes of the proteome in the conditional lethal Δ<i>bamB</i> Δ<i>bamE</i> double mutant. We show that cells lacking BamB and BamE have a global OMP defect that is a result of a lethal obstruction of an assembly-competent Bam complex by the lipoprotein RcsF. R2019-01-01T00:00:00Z2019 May2026-06-17T06:09:19.912Z2020-11-19T13:26:35ZS-EPMC65296383111390110.1128/mBio.00662-19