Glycine acylation and trafficking of a new class of bacterial lipoprotein by a composite secretion system
- University of Birmingham, United Kingdom
- University of Queensland, Australia
Abstract
Protein acylation is critical for many cellular functions across all domains of life. In bacteria, lipoproteins have important roles in virulence and are targets for the development of antimicrobials and vaccines. Bacterial lipoproteins are secreted from the cytosol via the Sec pathway and acylated on an N-terminal cysteine residue through the action of three enzymes. In Gram-negative bacteria, the Lol pathway transports lipoproteins to the outer membrane. Here we demonstrate that the Aat secretion system is a composite system sharing similarity with elements of a type I secretion systems and the Lol pathway. During secretion, the AatD subunit acylates the substrate CexE on a highly conserved N-terminal glycine residue. Mutations disrupting glycine acylation interfere with membrane incorporation and trafficking. Our data reveal CexE as the first member of a new class of glycine-acylated lipoprotein, while Aat represents a new secretion system that displays the substrate lipoprotein on the cell surface.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files
Article and author information
Author details
Jack Alfred Bryant
Funding
Biotechnology and Biological Sciences Research Council (DTP)
- Adam F Cunningham
- Ian R Henderson
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Icke 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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Glycine acylation and trafficking of a new class of bacterial lipoprotein by a composite secretion system
eLife 10:e63762.
https://doi.org/10.7554/eLife.63762
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