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The β-barrel assembly machinery in motion

Nature Reviews Microbiology volume 15, pages 197–204 (2017)Cite this article

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Abstract

In Gram-negative bacteria, the biogenesis of β-barrel outer membrane proteins (OMPs) is mediated by the β-barrel assembly machinery (BAM) complex. During the past decade, structural and functional studies have collectively contributed to advancing our understanding of the structure and function of the BAM complex; however, the exact mechanism that is involved remains elusive. In this Progress article, we discuss recent structural studies that have revealed that the accessory proteins may regulate essential unprecedented conformational changes in the core component BamA during function. We also detail the mechanistic insights that have been gained from structural data, mutagenesis studies and molecular dynamics simulations, and explore two emerging models for the BAM-mediated biogenesis of OMPs in bacteria.

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Figure 1: A journey towards the biogenesis of a β-barrel outer membrane protein.
Figure 2: The structures of the β-barrel assembly machinery complex.
Figure 3: Mechanistic models for the role of the BAM complex in OMP biogenesis.

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Acknowledgements

N.N. is supported by the Department of Biological Sciences at Purdue University, Indiana, USA, a Showalter Trust Award, and by the US National Institute of Allergy and Infectious Diseases (grant 1K22AI113078-01). J.C.G. is supported by a CAREER award from the US National Science Foundation (grant MCB-1452464); S.K.B. is supported by the Intramural Research Program of the US National Institute of Diabetes and Digestive and Kidney Diseases, part of the US National Institutes of Health.

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Authors and Affiliations

  1. Department of Biological Sciences and the Purdue Institute for Inflammation, Markey Center for Structural Biology, Immunology and Infectious Disease, Purdue University, West Lafayette, 47907, Indiana, USA

    Nicholas Noinaj

  2. School of Physics, Georgia Institute of Technology, Atlanta, 30332, Georgia, USA

    James C. Gumbart

  3. National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, 20892, Maryland, USA

    Susan K. Buchanan

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Correspondence to Nicholas Noinaj or Susan K. Buchanan.

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Noinaj, N., Gumbart, J. & Buchanan, S. The β-barrel assembly machinery in motion. Nat Rev Microbiol 15, 197–204 (2017). https://doi.org/10.1038/nrmicro.2016.191

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