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Annual Review of Microbiology

Volume 71, 2017

Outer Membrane Biogenesis

Abstract

The hallmark of gram-negative bacteria and organelles such as mitochondria and chloroplasts is the presence of an outer membrane. In bacteria such as , the outer membrane is a unique asymmetric lipid bilayer with lipopolysaccharide in the outer leaflet. Integral transmembrane proteins assume a β-barrel structure, and their assembly is catalyzed by the heteropentameric Bam complex containing the outer membrane protein BamA and four lipoproteins, BamB–E. How the Bam complex assembles a great diversity of outer membrane proteins into a membrane without an obvious energy source is a particularly challenging problem, because folding intermediates are predicted to be unstable in either an aqueous or a hydrophobic environment. Two models have been put forward: the budding model, based largely on structural data, and the BamA assisted model, based on genetic and biochemical studies. Here we offer a critical discussion of the pros and cons of each.

Keyword(s): envelope biogenesis, lateral gate, LptD, outer membrane protein, protein folding
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2017-09-08
2024-04-24
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Outer Membrane Biogenesis
Annual Review of Microbiology 71, 539 (2017); https://doi.org/10.1146/annurev-micro-090816-093754
/content/journals/10.1146/annurev-micro-090816-093754
/content/journals/10.1146/annurev-micro-090816-093754
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