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Structure and function of BamE within the outer membrane and the ?-barrel assembly machine.

ABSTRACT: Insertion of folded proteins into the outer membrane of Gram-negative bacteria is mediated by the essential ?-barrel assembly machine (Bam). Here, we report the native structure and mechanism of a core component of this complex, BamE, and show that it is exclusively monomeric in its native environment of the periplasm, but is able to adopt a distinct dimeric conformation in the cytoplasm. BamE is shown to bind specifically to phosphatidylglycerol, and comprehensive mutagenesis and interaction studies have mapped key determinants for complex binding, outer membrane integrity and cell viability, as well as revealing the role of BamE within the Bam complex.

SUBMITTER: Knowles TJ

PROVIDER: S-EPMC3049429 | biostudies-literature | 2011 Feb

REPOSITORIES: biostudies-literature

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Structure and function of BamE within the outer membrane and the β-barrel assembly machine.

Knowles Timothy J TJ Browning Douglas F DF Jeeves Mark M Maderbocus Riyaz R Rajesh Sandya S Sridhar Pooja P Manoli Eleni E Emery Danielle D Sommer Ulf U Spencer Ashley A Leyton Denisse L DL Squire Derrick D Chaudhuri Roy R RR Viant Mark R MR Cunningham Adam F AF Henderson Ian R IR Overduin Michael M

EMBO reports 20110107 2

Insertion of folded proteins into the outer membrane of Gram-negative bacteria is mediated by the essential β-barrel assembly machine (Bam). Here, we report the native structure and mechanism of a core component of this complex, BamE, and show that it is exclusively monomeric in its native environment of the periplasm, but is able to adopt a distinct dimeric conformation in the cytoplasm. BamE is shown to bind specifically to phosphatidylglycerol, and comprehensive mutagenesis and interaction st ...[more]

PMID: 21212804

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