1. Microbiology and Infectious Disease
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A lipoprotein/β-barrel complex monitors lipopolysaccharide integrity transducing information across the outer membrane

  1. Anna Konovalova
  2. Angela M Mitchell
  3. Thomas J Silhavy  Is a corresponding author
  1. Princeton University, United States
Research Article
  • Cited 36
  • Views 2,163
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Cite this article as: eLife 2016;5:e15276 doi: 10.7554/eLife.15276

Abstract

Lipoprotein RcsF is the OM component of the Rcs envelope stress response. RcsF exists in complexes with β-barrel proteins (OMPs) allowing it to adopt a transmembrane orientation with a lipidated N-terminal domain on the cell surface and a periplasmic C-terminal domain. Here we report that mutations that remove BamE or alter a residue in the RcsF trans-lumen domain specifically prevent assembly of the interlocked complexes without inactivating either RcsF or the OMP. Using these mutations we demonstrate that these RcsF/OMP complexes are required for sensing OM outer leaflet stress. Using mutations that alter the positively charged surface-exposed domain, we show that RcsF monitors lateral interactions between lipopolysaccharide (LPS) molecules. When these interactions are disrupted by cationic antimicrobial peptides, or by the loss of negatively charged phosphate groups on the LPS molecule, this information is transduced to the RcsF C-terminal signaling domain located in the periplasm to activate the stress response.

Article and author information

Author details

  1. Anna Konovalova

    Department of Molecular Biology, Princeton University, Princeton, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Angela M Mitchell

    Department of Molecular Biology, Princeton University, Princeton, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Thomas J Silhavy

    Department of Molecular Biology, Princeton University, Princeton, United States
    For correspondence
    tsilhavy@princeton.edu
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Michael A Marletta, University of California, Berkeley, United States

Publication history

  1. Received: February 15, 2016
  2. Accepted: June 7, 2016
  3. Accepted Manuscript published: June 10, 2016 (version 1)
  4. Version of Record published: July 12, 2016 (version 2)

Copyright

© 2016, Konovalova et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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