Defining the function of OmpA in the Rcs stress response
- Universite catholique de Louvain, Belgium
- Université Grenoble Alpes, CNRS, CEA, France
- Université Paul Sabatier, France
- Université Grenoble Alpes, France
Abstract
OmpA, a protein commonly found in the outer membrane of Gram-negative bacteria, has served as a paradigm for the study of b-barrel proteins for several decades. In Escherichia coli, OmpA was previously reported to form complexes with RcsF, a surface-exposed lipoprotein that triggers the Rcs stress response when damage occurs in the outer membrane and the peptidoglycan. How OmpA interacts with RcsF and whether this interaction allows RcsF to reach the surface has remained unclear. Here, we integrated in vivo and in vitro approaches to establish that RcsF interacts with the C-terminal, periplasmic domain of OmpA, not with the N-terminal b-barrel, thus implying that RcsF does not reach the bacterial surface via OmpA. Our results suggest a novel function for OmpA in the cell envelope: OmpA competes with the inner membrane protein IgaA, the downstream Rcs component, for RcsF binding across the periplasm, thereby regulating the Rcs response.
Data availability
All data generated or analyzed during this study are included in the manuscript and supporting files. Source data files have been provided for Figures 3, 4A, 4B, 5B, 5D and 6 supplement 1.
Article and author information
Author details
Jean-Francois Collet
Funding
Fonds pour la Formation à la Recherche dans l'Industrie et dans l'Agriculture
- Kilian Dekoninck
- Robin Bevernaegie
Fonds De La Recherche Scientifique - FNRS
- Kilian Dekoninck
- Juliette Létoquart
- Robin Bevernaegie
- Olivia Dehu
- Benjamin Elias
- Seung-Hyun Cho
FRFS-WELBIO
- Jean-Francois Collet
FRISBI (ANR-10-INBS-05-02)
- Cédric Laguri
- Jean-Pierre Simorre
GRAL
- Cédric Laguri
- Jean-Pierre Simorre
CBH-EUR-GS (ANR-17-EURE-0003)
- Cédric Laguri
- Jean-Pierre Simorre
Fédération Wallonie-Bruxelles (ARC 17/22-087)
- Jean-Francois Collet
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Dekoninck 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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Defining the function of OmpA in the Rcs stress response
eLife 9:e60861.
https://doi.org/10.7554/eLife.60861
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