A bacterial membrane sculpting protein with BAR domain-like activity
- Oak Ridge Institute for Science and Education / US Army DEVCOM Chemical Biological Center, United States
- University of Southern California, United States
- Wright-Patterson Air Force Base, United States
- US Naval Research Laboratory, United States
- California Institute of Technology, United States
- US Army DEVCOM Chemical Biological Center, United States
Abstract
Bin/Amphiphysin/RVS (BAR) domain proteins belong to a superfamily of coiled-coil proteins influencing membrane curvature in eukaryotes and are associated with vesicle biogenesis, vesicle-mediated protein trafficking, and intracellular signaling. Here we report a bacterial protein with BAR domain-like activity, BdpA, from Shewanella oneidensis MR-1, known to produce redox-active membrane vesicles and micrometer-scale outer membrane extensions (OMEs). BdpA is required for uniform size distribution of membrane vesicles and influences scaffolding of OMEs into a consistent diameter and curvature. Cryogenic transmission electron microscopy reveals a strain lacking BdpA produces lobed, disordered OMEs rather than membrane tubules or narrow chains produced by the wild type strain. Overexpression of BdpA promotes OME formation during planktonic growth of S. oneidensis where they are not typically observed. Heterologous expression results in OME production in Marinobacter atlanticus and Escherichia coli. Based on the ability of BdpA to alter membrane architecture in vivo, we propose that BdpA and its homologs comprise a newly identified class of bacterial BAR domain-like proteins.
Data availability
The mass spectrometry proteomics data have been deposited to the ProteomeXchange Consortium via the PRIDE [1] partner repository with the dataset identifier PXD020577.
Article and author information
Author details
Lauren Ann Metskas
Mohamed Y El-Naggar
Funding
U.S. Department of Defense
- Sarah M Glaven
Office of Naval Research (N00014-18-1-2632)
- Mohamed Y El-Naggar
National Science Foundation (DEB-1542527)
- Mohamed Y El-Naggar
U.S. Department of Energy (DE-FG02-13ER16415)
- Mohamed Y El-Naggar
National Institute of General Medical Sciences (GM122588)
- Grant J Jensen
U.S. Army Combat Capabilities Development Command (PE 0601102A Project VR9)
- Aleksandr E Miklos
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.
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A bacterial membrane sculpting protein with BAR domain-like activity
eLife 10:e60049.
https://doi.org/10.7554/eLife.60049
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