A lipoprotein/β-barrel complex monitors lipopolysaccharide integrity transducing information across the outer membrane
- Princeton University, United States
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
Reviewing Editor
- Michael A Marletta, University of California, Berkeley, United States
Version history
- Received: February 15, 2016
- Accepted: June 7, 2016
- Accepted Manuscript published: June 10, 2016 (version 1)
- 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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A lipoprotein/β-barrel complex monitors lipopolysaccharide integrity transducing information across the outer membrane
eLife 5:e15276.
https://doi.org/10.7554/eLife.15276
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