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The synthetic phenotype of bamBbamE double mutants results from a lethal jamming of the Bam complex by the lipoprotein RcsF

ABSTRACT: In Gram-negative bacteria, such as Escherichia coli, the heteropentomeric -barrel assembly machine (Bam) folds and inserts proteins into the outer membrane of the cell envelope. Here, we show that the conditional lethal phenotype of a mutant lacking two of the three nonessential lipoproteins, BamB and BamE, is caused by the lethal jamming of the stripped down Bam complex by a normally surface-exposed lipoprotein, RcsF. Our study highlights the importance of the nonessential Bam complex lipoproteins, BamB and BamE, in regulating the interaction between the essential Bam proteins, BamA and BamD and expands our understanding of the role of the Bam complex in outer membrane biogenesis.

INSTRUMENT(S): Orbitrap Fusion Lumos

ORGANISM(S): Escherichia Coli

SUBMITTER: Meera Gupta

LAB HEAD: Martin Wuehr

PROVIDER: PXD012335 | Pride | 2019-04-24

REPOSITORIES: Pride

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The 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.

Hart Elizabeth M EM Gupta Meera M Wühr Martin M Silhavy Thomas J TJ

mBio 20190521 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 O ...[more]

PMID: 31113901

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